Golf club head with l-shaped faceplate and weight pad

ABSTRACT

Embodiments of an iron-type golf club head comprising an L-shaped faceplate configured for flexibility are described herein. The L-shaped faceplate comprises a strike face portion and a sole return that wraps around a leading edge of the golf club head. In some embodiments, the L-shaped faceplate further comprises a top rail extension and a toe extension that extend to the peripheries of the golf club head. The golf club head comprises a rear body configured to receive the L-shaped faceplate to form a hollow interior cavity. The rear body comprises a sole ledge configured to receive the sole return. In some embodiments, the golf club head further comprises a weight pad that overhangs a portion of the sole return. In some embodiments, the golf club head further comprises dynamic lofting features that increase the bending in the rear body.

CROSS REFERENCE PRIORITIES

This is a continuation in part of U.S. patent application Ser. No.17/583,103, filed on Jan. 24, 2022, which claims the benefit of U.S.Provisional Application No. 63/282,577, filed Nov. 23, 2021; U.S.Provisional Application No. 63/263,936, filed Nov. 11, 2021; and U.S.Provisional Application No. 63/140,741, filed Jan. 22, 2021. Thisfurther claims priority to U.S. Provisional Application No. 63/500,880,filed May 8, 2023; U.S. Provisional Application No. 63/376,422, filedSep. 20, 2022; U.S. Provisional Application No. 63/376,059, filed Sep.16, 2022; and U.S. Provisional Application No. 63/371,453, filed Aug.15, 2022, all of which are incorporated in their entirety.

TECHNICAL FIELD

This disclosure relates generally to golf clubs and, more particularly,relates to golf club heads having increased energy transfer and golfclubs having laser welded faces.

BACKGROUND

Flexing and bending of a golf club head at the point of impact affectsthe launch characteristics of the golf ball being struck. The amount offlexure of the faceplate and/or other portions of the club head duringimpact influences the amount of energy transferred from the club head tothe ball as well as ball speed. Rearward bend of the faceplate at impact(hereafter “dynamic lofting”) further influences ball speed as well asthe launch angle of the ball. The dynamic loft of a golf club ismeasured as the amount of loft on the face of the club at the point ofimpact relative to a ground plane. Additional bending, or dynamiclofting, of a club head can increase the amount of spring energy storedby the golf club. The increased transfer of spring energy back to thegolf ball can increase the ball speed off the face for improved clubperformance. Thus, it would be advantageous to provide a golf club withimproved flexure, bending, and/or dynamic lofting characteristics.

BRIEF DESCRIPTION OF THE DRAWINGS

To facilitate further description of the embodiments, the followingdrawings are provided in which:

FIG. 1A illustrates a toe-side perspective view of a golf club headcomprising an L-shaped faceplate according to a first embodiment.

FIG. 1B illustrates a front view of the golf club head of FIG. 1A.

FIG. 2A illustrates a toe-side view of the golf club head of FIG. 1A.

FIG. 2B illustrates a top view of the golf club head of FIG. 1A.

FIG. 2C illustrates a sole view of the golf club head of FIG. 1A.

FIG. 2D illustrates a heel-side view of the golf club head of FIG. 1A.

FIG. 3 illustrates an exploded view of the faceplate and rear body ofthe golf club head of FIG. 1A.

FIG. 4 illustrates a toe-side cross-sectional view of the golf club headof FIG. 1A.

FIG. 5 illustrates a front view of the golf club of FIG. 1A with thefaceplate removed.

FIG. 6 illustrates a front view of the golf club head of FIG. 1A.

FIG. 7 illustrates a sole view of the golf club head of FIG. 1A.

FIG. 8 illustrates a toe-side perspective view of a golf club headcomprising an L-shaped faceplate according to a second embodiment.

FIG. 9 illustrates an exploded view of the faceplate and rear body ofthe golf club head of FIG. 8 .

FIG. 10 illustrates a toe-side cross sectional view of a golf club headwith an L-shaped faceplate and an angled weight pad.

FIG. 11 illustrates a zoomed-in view of FIG. 10 , focusing on the solereturn and the angled weight pad.

FIG. 12 illustrates a toe-side cross sectional view of a golf club headwith an L-shaped faceplate and a weight pad with an extension.

FIG. 13 illustrates a zoomed-in view of FIG. 12 , focusing on the solereturn and the weight pad with an extension.

FIG. 14 illustrates a toe-side cross-sectional view of the golf clubhead of FIG. 12 , highlighting the rear wall angle.

FIG. 15 illustrates a toe-side cross-sectional view of the golf clubhead of FIG. 12 , highlighting the upper interior undercut and the lowerinterior undercut.

FIG. 16 illustrates a rear perspective view of a golf club headcomprising a rear exterior cavity.

FIG. 17 illustrates a rear view of a golf club head comprising dynamiclofting features.

FIG. 18A illustrates a toe-side cross-sectional view of the golf clubhead of FIG. 17 .

FIG. 18B illustrates a zoomed in toe-side cross-sectional perspectiveview of the golf club head of FIG. 17 , focusing on the flexure hinge.

FIG. 18C illustrates a toe-side cross-sectional view of a golf club headin a different embodiment

FIG. 18D illustrates a zoomed in toe-side cross-sectional perspectiveview of the golf club head of FIG. 18C, focusing on the flexure hinge.

FIG. 19 illustrates a front-cross sectional view of the golf club headof FIG. 17 , highlighting the bending notch.

FIG. 20 illustrates a toe-side perspective view of a golf club headcomprising a toe port.

FIG. 21 illustrates a toe-side cross-sectional view of a golf club headcomprising a filled interior cavity.

FIG. 22 illustrates a front view of a hollow body club head according toan embodiment.

FIG. 23 illustrates a cross-sectional view of the golf club head of FIG.22 .

FIG. 24 illustrates a detailed cross-sectional view of the golf clubhead of FIG. 22 .

FIG. 25 illustrates a toe-side cross-sectional view of an iron-type golfclub head with an L-shaped faceplate and a continuous inner surface.

FIG. 26 illustrates a detailed view of the golf club head of FIG. 25 .

FIG. 27 illustrates a detailed view of the planes of the golf club headof FIG. 25 .

FIG. 28 illustrates an enlarged view of the golf club head of FIG. 25 .

FIG. 29 illustrates a toe-side cross-sectional view of an iron-type golfclub head with an L-shaped faceplate and a continuous inner surface withmultiple planar surfaces.

FIG. 30 illustrates a detailed view of the planes of the golf club headof FIG. 29 .

FIG. 31 illustrates a detailed view of the golf club head of FIG. 29 .

FIG. 32 illustrates a front view of the golf club head of FIG. 29 .

FIG. 33 illustrates a front view of heel and toe regions of the golfclub head of FIG. 30 .

FIG. 34 illustrates a toe-side cross-sectional view of an iron-type golfclub head with an L-shaped faceplate and an angled inner surface.

FIG. 35 illustrates a toe-side cross-sectional view of an iron-type golfclub head with an L-shaped faceplate and an angled, lower inner surface.

DEFINITIONS

The various embodiments of the golf club head described herein can beiron-type golf clubs or crossover-type golf clubs comprising an L-shapedfaceplate, sole ledge, and/or undercut to increase faceplate flexure,resulting in higher ball speeds. A rear body is coupled to the L-shapedfaceplate to enclose a hollow interior cavity, and the rear body canfurther include a rear portion configured to increase dynamic loft atimpact. The L-shaped faceplate may incorporate additional areas of theclub head that typically would be provided separate from a conventionalfaceplate, such as in the rear body. Furthermore, the L-shaped faceplatecan be formed of a material having a higher strength than that of therear body, thereby allowing the additional areas provided with theL-shaped faceplate to have reduced thickness without losing structuralintegrity. The reduced thickness increases flexure, leading to higherball speeds. In some embodiments, an internal weight pad is providedthat allows mass to be positioned lower in the golf club head. Theinternal weight pad extends over the sole return and forms an undercutthat prevents the faceplate from contacting the internal weight pad. Thesole ledge provides a buffer region between the L-shaped faceplate andthe rear body, and also prevents the internal weight pad frominterfering in the flexure of the L-shaped faceplate.

The club head can further comprise additional features that increasedynamic loft. For example, an internal surface of the rear portion canhave a bending notch, or cut-out portion, located near the toe end ofthe club head. Likewise, a rear wall of the rear body can have a flexurehinge, such as a groove or crease, that can be recessed in someembodiments and not recessed in other embodiments. The flexure hingeextends from a heel end of the club head to a toe end of the club head.The increased dynamic lofting of the club head achieved through saiddynamic lofting features leads to increased launch angle and ball speedsat impact.

The L-shaped faceplates described herein can include a sole return, atoe extension, a top rail extension, or any combination thereof. Each ofthese L-shaped faceplate embodiments can be combined with any of therear body embodiments described herein, which include rear bodies havinga sole ledge, an angled weight pad, a weight pad comprising anextension, a heel mass and/or toes mass, a lower interior undercut, anupper interior undercut, a rear exterior cavity, an external flexurehinge, an internal bending notch, an internal welding rib, or anycombination thereof.

For simplicity and clarity of illustration, the drawing figuresillustrate the general manner of construction, and descriptions anddetails of well-known features and techniques may be omitted to avoidunnecessarily obscuring the invention. Additionally, elements in thedrawing figures are not necessarily drawn to scale. For example, thedimensions of some of the elements in the figures may be exaggeratedrelative to other elements to help improve understanding of embodimentsof the present invention. The same reference numerals in differentfigures denote the same elements.

The terms “first,” “second,” “third,” “fourth,” and the like in thedescription and in the claims, if any, are used for distinguishingbetween similar elements and not necessarily for describing a particularsequential or chronological order. It is to be understood that the termsso used are interchangeable under appropriate circumstances such thatthe embodiments described herein are, for example, capable of operationin sequences other than those illustrated or otherwise described herein.Furthermore, the terms “include,” and “have,” and any variationsthereof, are intended to cover a non-exclusive inclusion, such that aprocess, method, system, article, device, or apparatus that comprises alist of elements is not necessarily limited to those elements but mayinclude other elements not expressly listed or inherent to such process,method, system, article, device, or apparatus.

The terms “left,” “right,” “front,” “back,” “top,” “bottom,” “over,”“under,” and the like in the description and in the claims, if any, areused for descriptive purposes and not necessarily for describingpermanent relative positions. It is to be understood that the terms soused are interchangeable under appropriate circumstances such that theembodiments of the invention described herein are, for example, capableof operation in other orientations than those illustrated or otherwisedescribed herein.

The terms “couple,” “coupled,” “couples,” “coupling,” and the likeshould be broadly understood and refer to connecting two or moreelements or signals, electrically, mechanically and/or otherwise.

The term “strike face,” as used herein, refers to a club head frontsurface that is configured to strike a golf ball. The term strike facecan be used interchangeably with the “face.”

The term “strike face perimeter,” as used herein, can refer to an edgeof the strike face. The strike face perimeter can be located along anouter edge of the strike face where the curvature deviates from a bulgeand/or roll of the strike face.

The term “geometric centerpoint,” as used herein, can refer to ageometric centerpoint 103 of the strike face perimeter, and at amidpoint of the face height of the strike face. In the same or otherexamples, the geometric centerpoint 103 also can be centered withrespect to an engineered impact zone, which can be defined by a regionof grooves on the strike face. As another approach, the geometriccenterpoint 103 of the strike face can be located in accordance with thedefinition of a golf governing body such as the United States GolfAssociation (USGA). For example, the geometric centerpoint 103 of thestrike face can be determined in accordance with Section 6.1 of theUSGA's Procedure for Measuring the Flexibility of a Golf Clubhead(USGA-TPX3004, Rev. 1.0.0, May 1, 2008) (available athttp://www.usga.org/equipment/testing/protocols/Procedure-For-Measuring-The-Flexibility-Of-A-Golf-Club-Head/)(the “Flexibility Procedure”).

The term “ground plane,” as used herein, can refer to a reference planeassociated with the surface on which a golf ball is placed. The groundplane can be a horizontal plane tangent to the sole at an addressposition.

The term “loft plane,” as used herein, can refer to a reference planethat is tangent to the geometric centerpoint of the strike face.

The term “loft angle,” as used herein, can refer to an angle measuredbetween the ground plane and the loft plane.

The term “effective depth” as used herein, can refer to the depth of thesole return that does not contact a portion of the rear body. In someembodiments, the effective depth is the depth of the sole return that isunhindered by the weight pad.

The golf club head comprises a coordinate system, centered about anorigin 125 point just off a leading edge of the strike face. The origin125 point is located where the loft plane intersects the ground plane123. The origin point is also within a vertical, front-to-rear planethat intersects the geometric centerpoint 103 of the strike face and isperpendicular to the ground plane. This coordinate system comprises anX-axis 127, a Y-axis 129, and a Z-axis. The X-axis 127 extends throughthe origin point 125 in a heel-to-toe direction and is positive towardsthe heel end of the club head. The Y-axis 129 extends through the originpoint in a sole-to-top rail direction and is positive towards the toprail. The Z-axis extends through the origin point in a front-to-reardirection and is positive towards the front.

The term “CG height” can refer to the CG location along the Y-axis,measured from the origin point.

DESCRIPTION

Referring to FIG. 1A, a hollow body club head 100 comprising an L-shapedfaceplate 150 and dynamic lofting features comprises a front end 102, arear end 104, a heel end 106, a toe end 108, a top rail 110, and a sole112. The L-shaped faceplate 150 comprises a strike face 116 at the frontend 102, with a loft plane 101 (FIG. 2 ) extending along the strike face116.

The top rail 110, heel end 106, toe end 108, and sole 112 extendrearward from a strike face perimeter 163 (FIG. 6 ) and form theperiphery of the club head 100. Referring to FIGS. 2A-2D, the club headperipheries are defined by the surfaces of the club head 100 that do notform part of the strike face 116 and which are located between the frontend 102 and the rear end 104. The strike face perimeter 163 extendsaround the strike face 116 and is defined as the points at which thefront end 102, apart from any grooves in the strike face 116, deviatesfrom being substantially planar. Referring to FIG. 2A, the club head 100defines a toe side periphery 124 extending along the toe end 108 betweenthe front end 102 and the rear end 104, and between the sole 112 and thetop rail 110. Referring to FIG. 2B, the club head 100 further defines atop rail periphery 126 extending along the top rail 110 between thefront end 102 and the rear end 104, and between the heel end 106 and thetoe end 108. Referring to FIG. 2C, the club head 100 further defines asole periphery 128 extending along the sole 112 between the front end102 and the rear end 104 and between the heel end 106 and the toe end108. Referring to FIG. 2D, the club head 100 further defines a heel sideperiphery 122 extending along the heel end 106 between the front end 102and the rear end 104 and between the sole 112 and the top rail 110.

I. L-shaped Faceplate

As illustrated in FIG. 1A, the club head 100 comprises the faceplate 150coupled to the rear body 130 at the front end 102. When viewed from theside and in cross-section, as shown in FIG. 4 , the faceplate 150generally has an “L-shape” comprising a strike face portion 152, whichextends along the loft plane 101, and a sole return 154. The strike faceperimeter 163 extends to the club head peripheries 122, 124, 126, 128,and the sole return 154 extends rearward from the strike face portion152 and forms a portion of the sole 112, as best illustrated withreference to FIGS. 3, 4, 6, and 7 . The geometry and arrangement of thefaceplate 150 allows the faceplate 150 and portions of the rear body 130to have reduced thickness(es) without sacrificing structural integrity,such that the faceplate 150 provides a club head 100 with increasedfaceplate flexure and ball speed.

As illustrated in FIG. 3 , the club head 100 comprises a hollow bodyconstruction formed by the L-shaped faceplate 150 coupled to a rear body130, enclosing a hollow interior cavity 114. The rear body 130 comprisesa rear body top rail portion 132, a rear body sole portion 138, a rearbody heel portion 134, a rear body toe portion 136, a hosel 142, and arear wall 140. The rear wall 140 extends upward from the rear body soleportion 138 to the top rail portion 132 and encloses the rear end 104 ofthe club head 100. The rear body 130 further defines a rear body opening144 proximate the front end 102 of the club head 100. The rear bodyopening 144 is defined between the rear body top rail portion 132, therear body heel portion 134, the rear body toe portion 136, and the rearbody sole portion 138. Referring to FIG. 5 , a plurality of weldingsurfaces 146 extend around a perimeter of the rear body opening 144. Thewelding surfaces 146 are formed by forwardmost edges of the rear bodytop rail portion 132, rear body heel portion 134, rear body toe portion136, and rear body sole portion 138. The welding surfaces 146 provide aninterface for the faceplate 150 and the rear body 130 to be coupledtogether. In many embodiments the welding surfaces 146 can be asubstantially flat surface configured to receive the faceplate 150thereon.

The rear body 130 further comprises a plurality of weighting featuresdesigned to lower the center of gravity (CG) of the club head 100.Referring to FIG. 10 , the rear body 130 can comprise a weight pad 1000located in a low and rearward position of the interior cavity 114. Theweight pad 1000 is integrally formed with both the rear body soleportion 138 and the rear wall 140. The weight pad 1000 can have a lowprofile and can concentrate a large amount of mass low in the club head100. The weight pad 1000 extends a majority of the distance between therear body heel portion 134 and the rear body toe portion 136, as bestshown in FIG. 5 .

Referring to FIG. 5 , the rear body 130 can further comprise a heel mass147 and a toe mass 149 located within the lower heel and lower toe areasof the interior cavity 114, respectively. The heel mass 147 and the toemass 149 increase the perimeter weight of the club head 100, therebyincreasing the club head moment of inertia in the heel-to-toe direction.The heel mass 147 can be integrally formed with the rear body soleportion 138, the rear body heel portion 134, and the rear wall 140. Thetoe mass 149 can be integrally formed with the rear body sole portion138, the rear body toe portion 136, and the rear wall 140. In manyembodiments, the heel and toe masses 147, 149 are integral with theweight pad 1000, as illustrated in FIG. 5 . The placement of the heelmass 147 and the toe mass 149 in the low, rearward heel and toe portionsof the interior cavity 114 provides a lower CG position and increasedheel-to-toe moment of inertia, in comparison to a club head devoid of aheel mass and/or toe mass. The placement of the heel mass 147 and thetoe mass 149 improves these club head characteristics withoutinterfering with the flexure of the L-shaped faceplate 150.

Referring again to FIGS. 4 and 5 , the rear body 130 further defines asole ledge 148 on the rear body sole portion 138. The sole ledge 148 canbe combined with any faceplate geometry described above or belowincluding the sole return 154, a top rail extension 170, a toe extension168, or any combination thereof. The sole ledge 148 is formed integrallywith the rear body 130 and is located immediately forward of the weightpad 1000. The sole ledge 148 protrudes forward from the weight pad 1000and extends from near the heel end 106 to near the toe end 108, alongthe extent of the weight pad 1000. The sole ledge 148 comprises a soleledge front surface 151, which is the forwardmost surface of the soleledge 148. The sole ledge front surface 151 forms the welding surfaces146 along the sole 112 and provides a surface to easily attach the solereturn 154 to the rear body sole portion 138. Specifically, the soleledge front surface 151 contacts a sole perimeter edge 166 of thefaceplate 150, as discussed in further detail below. In manyembodiments, the sole perimeter edge 166 is the only portion of the solereturn 154 that contacts the rear body 130. The sole ledge 148 forms asection of the sole 112 and separates the sole return 154 from theweight pad 1000.

The sole ledge 148 forms a relatively small section of the sole 112.Referring to FIG. 11 , the sole ledge 148 defines a sole ledge depth 153measured from a weight pad front wall 1010 to the faceplate soleperimeter edge 166. In some embodiments, the sole ledge depth 153 variesin a heel to toe direction. In other embodiments, the sole ledge depth153 is constant in a heel to toe direction. The sole ledge depth 153 canbe between 0.01 inch to 0.20 inch. In some embodiments, the sole ledgedepth 153 is between 0.01 inch to 0.05 inch, 0.03 inch to 0.07 inch,0.05 inch to 0.10 inch, 0.07 inch to 0.10 inch, 0.09 inch to 0.12 inch,0.10 inch to 0.15 inch, 0.13 inch to 0.17 inch, 0.15 inch to 0.20 inch,or 0.17 inch to 0.20 inch. In some embodiments, the sole ledge depth 153is approximately 0.01 inch, 0.02 inch, 0.03 inch, 0.04 inch, 0.05 inch,0.06 inch, 0.07 inch, 0.08 inch, 0.09 inch, 0.10 inch, 0.11 inch, 0.12inch, 0.13 inch, 0.14 inch, 0.15 inch, 0.16 inch, 0.17 inch, 0.18 inch,0.19 inch, or 0.20 inch. In one exemplary embodiment, the sole ledgedepth 153 is 0.09 inch. The sole ledge depth 153 is sufficiently largeto move the faceplate 150 away from the weight pad 1000, whileincreasing a sole return depth 158 (FIG. 7 ). The sole ledge depth 153is selected to increase the flexure of the faceplate 150. As discussedabove, increasing the flexure of the faceplate 150 transfers more energyto the golf ball, producing faster ball speeds.

As discussed in further detail below, the sole ledge depth 153 isselected to increase the sole return depth 158 while providingsufficient distance between the sole return 154 and the weight pad 1000,so that the weight pad 1000 does not contact the sole return 154. If thesole ledge 148 was omitted, the weight pad 1000 would contact the solereturn 154 and the sole return depth 158 would effectively be shortened,reducing the flexure of the faceplate 150. To further increase theflexure of the faceplate 150, the sole ledge 148 comprises a thicknessthat is identical or substantially similar to the thickness of the solereturn 154, as discussed in greater detail below.

The sole ledge 148 further provides manufacturing advantages. The soleledge 148 requires only a single surface (i.e., the sole perimeter edge166) of the sole return 154 to contact the rear body 130. Some golf clubheads devoid of a sole ledge require multiple surfaces of the solereturn to contact the rear body. For example, some golf club headsrequire the sole perimeter edge and a portion of the interior surfaceboth to contact the rear body. Each surface of the sole return 154 thatcontacts the rear body 130 must be prepared, and preparing additionalsurfaces increases the cost of manufacturing. Therefore, the sole ledge148 reduces manufacturing costs by requiring only a single surface ofthe sole return 154 to be prepared.

Further, the sole ledge 148 simplifies assembly of the faceplate 150with the rear body 130. More specifically, the sole return 154 requiresonly a single surface of the sole return 154 to be aligned with a singlesurface of the rear body 130. Some golf club heads devoid of a soleledge provide a more complicated receiving geometry, where multiplesurfaces of the sole return must align with multiple surfaces of therear body. Each additional surface lowers the margin of error allowedwhen aligning the sole return 154 with the rear body 130. The lowermargin of error requires the sole ledge 148 to be formed within tightertolerances, which can increase costs and complicate manufacturing of thefaceplate 150. Therefore, the club head 100 comprising the sole ledge148 is easier and cheaper to manufacture than a golf club devoid of asole ledge.

The sole ledge 148 advantageously defines a buffer region between thesole return 154 and the weight pad 1000. As discussed above, the solereturn 154 only contacts the rear body 130 at the sole ledge frontsurface 151. In some golf club heads devoid of a sole ledge, the rearbody overlaps the sole return such that multiple surfaces of the solereturn contact the rear body. For example, in some golf club headsdevoid of a sole ledge, the sole return extends into a weight pad suchthat the weight pad overlaps the rearmost portion of the sole return.Each additional surface that contacts or covers the sole return 154 caninhibit bending as the effective depth of the sole return 154 isdecreased. In such embodiments, less energy is stored at impact andreleased back into the golf ball, leading to decreased ball speed incomparison to a club head comprising a sole ledge 148.

In the embodiments described herein, the sole ledge 148 projects fromthe weight pad front wall 1010 such that the sole ledge 148 blocks thesole return 154 from contacting the weight pad 1000. The sole ledgefront surface 151 is the only portion of the rear body 130 that contactsthe faceplate sole perimeter edge 166. The sole return interior surface161 does not contact any portion of the weight pad 1000, and even morespecifically, the sole return interior surface 161 does not contact theweight pad front wall 1010. Instead, a smooth transition is defined fromthe sole ledge 148 to the sole return 154.

Referring to FIG. 1A, the club head 100 comprises the L-shaped faceplate150 configured to increase flexure, thereby increasing ball speed. TheL-shaped faceplate 150 is coupled to the rear body 130 at the weldingsurfaces 146, thereby covering the rear body opening 144 and enclosingthe hollow interior cavity 114. The faceplate 150 can be formed from adifferent material than the material of the rear body 130. For example,the faceplate 150 can comprise a material with a greater strength thanthe rear body material.

In many embodiments, the rear body material is selected to facilitatecasting into the rear body, which may have a complex geometry. In manyembodiments, the rear body material is a stainless steel, such as 17-4stainless steel. In other embodiments, the rear body material can be asteel or stainless steel alloy such as 15-5 stainless steel, 431stainless steel, 4140 steel, 4340 steel, or any other material suitablefor casting into the complex geometries of the rear body 130.

In many embodiments, the yield strength of the rear body material canrange between approximately 60 ksi and approximately 140 ksi. In someembodiments, the yield strength of the rear body material can be between60 ksi and 70 ksi, 70 ksi and 80 ksi, 80 ksi and 90 ksi, 90 ksi and 100ksi, 100 ksi and 110 ksi, 110 ksi and 120 ksi, 120 ksi and 130 ksi, or130 ksi and 140 ksi. In some embodiments, the yield strength of the rearbody material can be greater than 60 ksi, greater than 70 ksi, greaterthan 80 ksi, greater than 90 ksi, greater than 100 ksi, greater than 110ksi, greater than 120 ksi, or greater than 130 ksi.

The faceplate material can be a higher strength material than the rearbody material. In many embodiments, the faceplate material can be amaraging steel such as C300. In other embodiments, the faceplatematerial can be a high-strength steel or steel alloy, C250, C350,AerMet® 100, AerMet® 310, AerMet® 340, HSR300, K300 or any otherhigh-strength material suitable of being formed into an L-shapedfaceplate.

In many embodiments, the yield strength of the faceplate material canrange between approximately 220 ksi and approximately 300 ksi. In someembodiments, the yield strength of the faceplate material can be between220 ksi and 230 ksi, 230 ksi and 240 ksi, 240 ksi and 250 ksi, 250 ksiand 260 ksi, 260 ksi and 270 ksi, 270 ksi and 280 ksi, 280 ksi and 290ksi, or 290 ksi and 300 ksi. In some embodiments, the yield strength ofthe rear body material can be greater than 220 ksi, greater than 230ksi, greater than 240 ksi, greater than 250 ksi, greater than 260 ksi,greater than 270 ksi, greater than 280 ksi, or greater than 290 ksi.

In many embodiments, elastic modulus of the faceplate material can besubstantially the same as the elastic modulus of the rear body material.This means that while the faceplate material is stronger than the rearbody material, the faceplate material and the rear body materialcomprise similar flexibility. Increased flexure in the club head 100 canbe achieved by replacing the low-strength rear body material with thehigher strength faceplate material having a similar elastic modulus.This allows the portions of the rear body 130 replaced by the faceplatematerial to be thinned without sacrificing the flexibility of thematerial or the structural integrity in said portions.

In many embodiments, the elastic modulus of the faceplate material canrange between 170 GPa to 220 GPa. In some embodiments, the elasticmodulus of the faceplate material can be between 170 GPa and 180 GPa,between 180 GPa and 190 GPa, between 180 GPa and 190 GPa, between 190GPa and 200 GPa, between 200 GPa and 210 GPa, or between GPa 210 and 220GPa. In many embodiments, the elastic modulus of the faceplate materialcan be greater than 170 GPa, greater than 175 GPa, greater than 180 GPa,greater than 185 GPa, greater than 190 GPa, greater than 195 GPa,greater than 200 GPa, greater than 205 GPa, greater than 210 GPa,greater than 215 GPa, or greater than 220 GPa, The combination of a highyield strength and a high modulus of elasticity provides the faceplatematerial with the ability to thin portions of the club head 100 andincrease flexibility without sacrificing structural integrity.

As mentioned above, the L-shaped faceplate 150 comprises a strike faceportion 152 extending along the loft plane 101 from the sole 112 to thetop rail 110, and a sole return 154 forming a portion of the sole 112.The L-shaped faceplate 150 forming a sole return 154 can be combinedwith any rear body 130 geometry or feature described either above orbelow, including a sole ledge 148, an angled weight pad 1000, a weightpad 2000 comprising an extension 2050, a heel mass 147 and/or toes mass149, a lower interior undercut 190, an upper interior undercut 195, arear exterior cavity 198, an external flexure hinge 3000, an internalbending notch 3100, an internal welding rib 179, or any combinationthereof.

The sole return 154 extends rearward from the leading edge 118. Asillustrated in FIG. 4 , the faceplate 150 forms an “L” shape when viewedfrom a side cross-section, wherein the L-shaped faceplate 150 wraps overthe leading edge 118 to the sole 112. The leading edge 118 forms an“elbow” of the L shape. The leading edge 118 serves as a junction ortransition between the strike face portion 152 and the sole return 154of the L-shaped faceplate 150.

The sole return 154 allows the L-shaped faceplate 150 to flex greaterthan a similar faceplate devoid of a sole return 154. The sole return154 forms portions of the sole 112 that would otherwise be provided withthe rear body 130 using faceplate material. In many embodiments, thefaceplate material comprises a higher yield strength than the rear bodymaterial, while retaining a similar elastic modulus as the rear bodymaterial. Portions of the rear body sole portion 138 that are replacedby the sole return 154 can have reduced thickness without sacrificingstructural integrity, thereby increasing flexure. The additional flexureassociated with the inclusion of the sole return increases energytransfer between the strike face 116 and the golf ball at impact,resulting in a club head 100 that effects increased ball speed.

The sole return 154 further increases flexure in the club head 100 byallowing the sole 112 and the faceplate 150 to have reduced thicknesseswithout sacrificing structural integrity. In some golf clubs, structuralfailure commonly occurs along high stress areas located at the leadingedge or portions of the sole proximate the strike face. In some golfclubs, the sole is constructed of a relatively low-strength castmaterial, so the thickness of portions of the sole and/or the strikeface must be increased to provide the necessary structural integrity inthe high stress areas. The sole return 154 replaces lower-strength rearbody material with higher-strength faceplate material at high stressareas. Placing high strength faceplate material in peak stress regions(such as on the sole proximate the leading edge 118) allows the strikeface 116 and the sole 112 to have reduced thicknesses, therebyincreasing flexure and resulting ball speed without sacrificingdurability.

In many embodiments, the sole return 154 allows the strike face 116 tohave a reduced thickness, increasing the strike face 116 flexure. Inmany embodiments, the strike face 116 has a variable thickness. Forexample, the strike face 116 may include a thickened region 172 near thecenter of the strike face 116, as illustrated in FIG. 4 . The thickenedregion 172 may define a maximum thickness of the strike face 116. Areasof the strike face 116 located away from the thickened region 172 andcloser to the perimeter of the strike face 116 can define a minimumthickness of the strike face 116. In many embodiments, the maximumthickness of the strike face 116 can range from approximately 0.085 inchto approximately 0.100 inch. In some embodiments, the maximum thicknessof the strike face 116 can be between 0.085 inch and 0.0875 inch,between 0.085 inch and 0.090 inch, between 0.085 inch and 0.0925 inch,or between 0.085 inch and 0.095 inch. In many embodiments, the minimumthickness of the strike face 116 can range from approximately 0.060 inchto approximately 0.075 inch. In some embodiments, the minimum thicknessof the strike face 116 can be between 0.060 inch and 0.0625 inch,between 0.060 inch and 0.065 inch, between 0.060 inch and 0.0675 inch,between 0.060 inch and 0.070 inch, or between 0.060 inch and 0.0725inch. The thicknesses of the different portions of the strike face 116can be selected to increase the flexure of the faceplate 150.

The sole return 154 allows the strike face 116 to be uniformly reducedin thickness without sacrificing durability. The sole return 154 allowsthe thickness of the strike face 116 to be reduced (with respect to asimilar club head devoid of a sole return) by greater than 0.001 inch,greater than 0.0025 inch, greater than 0.005 inch, greater than 0.0075inch, greater than 0.010 inch, greater than 0.0125 inch, greater than0.0150 inch, greater than 0.0175 inch, or greater than 0.020 inch. Asdiscussed above, reducing thickness of the strike face 116 increases theflexure of the faceplate 150.

Similarly, in many embodiments, the sole return 154 allows portions ofthe sole 112 near the leading edge 118 to have reduced thickness,increasing flexure of the faceplate 150 and sole 112. In manyembodiments, the thickness of the sole return 154 can range fromapproximately 0.030 inch to approximately 0.060 inch. In someembodiments, the thickness of the sole return 154 can be between 0.035inch and 0.045 inch, between 0.040 inch and 0.050 inch, between 0.045inch and 0.055 inch, or between 0.050 inch and 0.060 inch. In someembodiments, the thickness of the sole return 154 can be between 0.030inch and 0.035 inch, between 0.030 inch and 0.040 inch, between 0.030inch and 0.045 inch, between 0.030 inch and 0.050 inch, between 0.030inch and 0.055 inch, or between 0.030 inch and 0.060 inch. The thicknessof the sole return 154 is selected to increase the flexure of thefaceplate 150 while providing structural integrity to the leading edge118.

The sole return 154 allows the portion of the sole 112 proximate theleading edge 118 (i.e., where the sole return is located) to be thinnerthan that of a similar club head devoid of a sole return by greater thanapproximately 0.001 inch, greater than 0.0025 inch, greater than 0.005inch, greater than 0.0075 inch, greater than 0.010 inch, greater than0.0125 inch, greater than 0.0150 inch, greater than 0.0175 inch, orgreater than 0.020 inch. The reduced thickness of the leading edge 118promotes bending to increase the flexure of the faceplate 150.

The sole return 154 further allows the sole ledge 148, which is rearwardof the sole return 154 and forward of the weight pad 1000, to have areduced thickness without sacrificing structural integrity. In manyembodiments, the sole ledge 148 comprises a thickness that is identical,or substantially similar, to the thickness of the sole return 154, asillustrated in FIG. 11 . Providing a sole ledge thickness that issimilar to that of the sole return thickness increases flexibility ofthe sole return 154. By providing a substantially thin sole ledge 148,the sole return 154 and the sole ledge 148 combine to form a continuous,thin sole portion of a substantially constant thickness. Although thesole ledge 148 may be formed of the lower-strength rear body material,the sole ledge 148 can be equally as thin as the higher-strength solereturn 154, because the sole ledge 148 is located further rearward ofthe peak stresses occurring at the leading edge 118. Further, thesimilarity in the elastic moduli of the rear body material forming thesole ledge 148 and the faceplate material forming the sole return 154allows the thin sole portion to bend without breaking.

In many embodiments, the sole ledge 148 has a thickness similar to thatof the sole return 154, and may range from approximately 0.030 inch toapproximately 0.060 inch. In some embodiments, the thickness of the soleledge 148 can be between 0.035 inch and 0.045 inch, between 0.040 inchand 0.050 inch, between 0.045 inch and 0.055 inch, or between 0.050 inchand 0.060 inch. In some embodiments, the thickness of the sole ledge 148can be between 0.030 inch and 0.035 inch, between 0.030 inch and 0.040inch, between 0.030 inch and 0.045 inch, between 0.030 inch and 0.050inch, between 0.030 inch and 0.055 inch, or between 0.030 inch and 0.060inch. The similar thickness of the sole ledge 148 and the sole return154 creates a smooth transition from the rear body 130 to the faceplate150.

A. L-shaped Faceplate with Top Rail Extension and Toe Extension

In many embodiments, as illustrated by FIG. 6 , the L-shaped faceplate150 extends beyond the strike face perimeter 163. The faceplate 150 cancomprise a toe extension 168 and a top rail extension 170, wherein theedges of the faceplate 150 extend all the way to the club headperipheries 122, 124, 126, 128. The L-shaped faceplate 150 comprising atoe extension 168 and a top rail extension 170 can be combined with anyrear body 130 geometry or feature described either above or below,including a sole ledge 148, an angled weight pad 1000, a weight pad 2000comprising an extension 2050, a heel mass 147 and/or toes mass 149, alower interior undercut 190, an upper interior undercut 195, a rearexterior cavity 198, an external flexure hinge 3000, an internal bendingnotch 3100, an internal welding rib 179, or any combination thereof.

The L-shaped faceplate 150 comprising a toe extension 168 and a top railextension 170 forms at least a portion of the top rail 110 and a portionof the toe end 108. The geometry of the L-shaped faceplate 150 can bedefined by a plurality of edges forming a faceplate perimeter. TheL-shaped faceplate 150 can comprise a top perimeter edge 160, a heelside perimeter edge 162, a toe side perimeter edge 164, and a soleperimeter edge 166, as illustrated in FIGS. 3 and 4 .

Referring to FIGS. 2A, 2B, and 4 , via the top rail extension 170, thefaceplate 150 extends to the top rail periphery 126, and the topperimeter edge 160 is located on the top rail 110. Similarly, via thetoe extension 168, the faceplate 150 extends to the toe side periphery124, and the toe side perimeter edge 164 is located on the toe end 108.Via the sole return 154, the faceplate 150 extends all the way to thesole periphery 128, and the sole perimeter edge 166 is located on thesole 112. The faceplate 150 forms at least a portion of the top rail110, at least a portion of the toe end 108, and at least a portion ofthe sole 112. As such, the top perimeter edge 160, the toe sideperimeter edge 164, and the sole perimeter edge 166 are all located onthe club head peripheries 122, 124, 128 and are located away the strikeface 116. The heel side perimeter edge 162 is located on the front end102 of the club head 100 and serves as a boundary of the strike face 116on the heel end 106. The heel side perimeter edge 162 separates thehosel 142 from the strike face 116.

The perimeter edges of the faceplate 150 provide an interface betweenthe faceplate 150 and the rear body 130. Referring to FIG. 4 , theperimeter edges of the faceplate 150 are welded to the welding surfaces146 of the rear body 130, coupling the faceplate 150 to the rear body130. A plurality of weld lines is defined between the faceplate 150 andthe rear body 130 at the interface between the faceplate perimeter edgesand the rear body welding surfaces 146. In many embodiments, thefaceplate 150 and the rear body 130 are welded together via a laserwelding process.

In many embodiments, each of the perimeter edges of the faceplate 150,specifically the top perimeter edge 160, the toe side perimeter edge164, the top rail extension 170, the toe extension 168, and the soleperimeter edge 166, comprises a bevel or chamfer, as illustrated in FIG.4 . The bevels and/or chamfers of the toe extension 168 and top railextension 170 provides a smooth transition from the strike face 116 tothe toe side periphery 124, and the top rail periphery 126,respectively. For example, the toe extension 168 forms a bevel at thetransition between the strike face 116 and the toe end 108, while thetop rail extension 170 forms a bevel at the transition between thestrike face 116 and the top rail 110.

The geometry of the faceplate 150 and the placement of the faceplateperimeter edges on the club head periphery increases flexure in thefaceplate 150 by moving the weld line off the strike face 116. Manyprior art hollow body irons comprise a non L-shaped face insert attachedto the front surface of the club head to form the hollow interiorcavity. In such prior art club heads, the insert is situated internallywith respect to the club head peripheries, and every weld line betweenthe face insert and the body is located on the strike face. The weldlines of the prior art clubs contribute to the thickness of the strikeface and reduce the flexibility of the faceplate. The additionalthickness created by the weld lines reduces the ability of the faceplateto flex. In contrast, the L-shaped faceplate 150 comprising a solereturn 154, a toe extension 168, and a top rail extension 170 does notform any weld lines on the strike face 116. Instead, the weld lines arelocated on the club head peripheries 122, 124, 128, increasing flexureof the faceplate 150.

Referring to FIG. 4 , in many embodiments, the L-shaped faceplate 150does not form a return portion on the top rail 110 or the toe end 108.The strike face comprises a strike face back surface 156 that issubstantially flat proximate the top rail 110 and along the heel end106. No portion of the faceplate 150 near the toe end 108 or the toprail 110 extends rearward from the strike face back surface 156 or formsa return. In this way, the faceplate 150 is L-shaped with a straightstrike face portion 152 and a sole return 154 near the sole 112, asopposed to a cup-shaped faceplate comprising return portions on the topand/or toe end of the strike face portion. The various embodiments ofthe L-shaped faceplate 150 described herein are designed to increase theflexure of the faceplate 150.

The faceplate 150 comprises a faceplate surface area measured across thefaceplate 150 and bounded by the top perimeter edge 160, the toe sideperimeter edge 164, the heel side perimeter edge 162, and the leadingedge 118. The faceplate surface area correlates to the spring-likeeffect of the faceplate 150. As the faceplate surface area increases,the spring-like effect of the faceplate 150 increases, which increasesthe flexure of the faceplate 150. The increased flexing allows thefaceplate 150 to transfer more energy to the golf ball, which producesfaster ball speeds.

In some embodiments, the faceplate surface area is between approximately3.50 in² to approximately 5.00 in². In some embodiments, the faceplatesurface area is between 3.50 in² to 3.75 in², 3.65 in² to 3.90 in², 3.80in² to 4.20 in², 4.00 in² to 4.25 in², 4.25 in² to 4.50 in², 4.50 in² to4.75 in², or 4.70 in² to 5.00 in². In some embodiments, the faceplatesurface area is approximately 3.50 in², 3.55 in², 3.60 in², 3.65 in²,3.70 in², 3.75 in², 3.80 in², 3.85 in², 3.90 in², 3.95 in², 4.00 in²,4.05 in², 4.10 in², 4.15 in², 4.20 in², 4.25 in², 4.30 in², 4.35 in²,4.30 in², 4.35 in², 4.40 in², 4.45 in², 4.50 in², 4.55 in², 4.60 in²,4.65 in², 4.70 in², 4.75 in², 4.80 in², 4.85 in², 4.90 in², 4.95 in², or5.00 in². The faceplate surface area is selected to promote the flexureof the faceplate 150.

In some embodiments, the faceplate 150 comprising a top rail extension170 and a toe extension 168 comprises a larger faceplate surface areathan a faceplate devoid of these features. In some embodiments, thefaceplate surface area is between approximately 5.00 in² toapproximately 6.00 in². In some embodiments, the faceplate surface areais between 5.00 in² to 5.30 in², 5.15 in² to 5.25 in², 5.20 in² to 5.40in², 5.35 in² to 5.60 in², 5.50 in² to 5.70 in², or 5.60 in² to 6.00in². In some embodiments, the faceplate surface area is approximately5.00 in², 5.05 in², 5.10 in², 5.15 in², 5.20 in², 5.25 in², 5.30 in²,5.35 in², 5.30 in², 5.35 in², 5.40 in², 5.45 in², 5.50 in², 5.55 in²,5.60 in², 5.65 in², 5.70 in², 5.75 in², 5.80 in², 5.85 in², 5.90 in²,5.95 in², or 6.00 in². The surface area of the faceplate 150 is selectedto promote the flexure of the faceplate 150.

In some embodiments, the surface area of the faceplate 150 comprising atop rail extension 170 and a toe extension 168 is between approximately1.00 in² to approximately 3.00 in² larger than a faceplate devoid ofthese features. In some embodiments, the surface area of the faceplate150 is between 1.00 in² to 1.25 in², 1.20 in² to 1.50 in², 1.40 in² to1.75 in², 1.50 in² to 2.00 in², 1.75 in² to 2.25 in², 2.20 in² to 2.50in², 2.40 in² to 2.75 in², or 2.50 in² to 3.00 in² larger than thesurface area of the faceplate devoid of a top rail extension and a toeextension. The increased surface area of the faceplate 150 comprising atoe extension 168 and a top rail extension 170 promotes increasedflexure in the faceplate 150.

Referring to FIG. 4 , the contour of the sole perimeter edge 166determines the shape of the sole return 154. At the sole return 154, thesole perimeter edge 166 extends rearward along the sole 112 and servesas a boundary between the L-shaped faceplate 150 and the rear body soleportion 138. The sole return 154 can be complementarily shaped to sitflush against the sole ledge 148. The contour of the welding surfaces146 at the rear body sole portion 138 can correspondingly match thecontour of the sole perimeter edge 166 on the sole return 154. Thecomplementary geometry of the sole return 154 and the rear body soleportion 138 creates a continuous sole surface formed without any gaps orslots in between the rear body 130 and the faceplate 150.

Referring to FIGS. 3, 4, and 7 , in many embodiments, the sole perimeteredge 166 can comprise a rear sole perimeter edge 166 a, a heel-side soleperimeter edge 166 b, and a toe-side sole perimeter edge 166 c. As bestshown in FIG. 7 , the heel-side sole perimeter edge 166 b and thetoe-side sole perimeter edge 166 c can extend rearwardly from theleading edge 118 at an angle, and the rear sole perimeter edge 166 a canextend between the heel-side sole perimeter edge 166 b and the toe-sidesole perimeter edge 166 c in a heel-to-toe direction, substantiallyparallel to the leading edge 118.

In many embodiments, the sole return 154 does not extend rearward fromthe entire length of the leading edge 118. Referring to FIG. 7 , thesole return 154 defines a sole return width 157 measured in aheel-to-toe direction. In many embodiments, the sole return width 157can be less than the length of the leading edge 118, such that the solereturn 154 does not span the entire leading edge 118 or the entire sole112 in a heel-to-toe direction from the heel-side sole perimeter edge166 b to the toe-side sole perimeter edge 166 c. In some embodiments,the sole return width 157 can be tapered such that the width graduallydecreases from proximate the leading edge 118 toward the rear soleperimeter edge 166 a. In such embodiments, the sole return 154 cancomprise a maximum width proximate the leading edge 118 and a minimumwidth at the rear sole perimeter edge 166 a. In some embodiments, thesole return 154 may not be tapered and the sole return width 157 can beconstant in a front-to-rear direction.

The rate at which the sole return width 157 decreases can becharacterized by a plurality of taper angles β_(t), β_(h). Referring toFIG. 7 , the plurality of taper angles β_(t), β_(h) can be measured asexterior angles between the sole perimeter edge 166 and the leading edge118. The sole return 154 can comprise a heel-side taper angle β_(h)measured between the heel-side sole perimeter edge 166 b and the leadingedge 118 and a toe-side taper angle β_(t) measured between the toe-sidesole perimeter edge 166 c and the leading edge 118. In many embodiments,the heel-side taper angle β_(h) and the toe-side taper angle β_(t) canbe the same or substantially similar. In other embodiments, theheel-side taper angle β_(h) and the toe-side taper angle β_(t) can bedifferent.

In many embodiments, the heel-side taper angle β_(h) can range betweenapproximately 100 degrees and approximately 160 degrees. In manyembodiments, the heel-side taper angle β_(h) can be between 100 degreesand 110 degrees, between 110 degrees and 120 degrees, between 120degrees and 130 degrees, between 130 degrees and 140 degrees, between140 degrees and 150 degrees, or between 150 degrees and 160 degrees. Inmany embodiments, the heel-side taper angle β_(h) can be between 110degrees and 130 degrees, between 115 degrees and 135 degrees, between120 degrees and 140 degrees, between 125 degrees and 145 degrees,between 130 degrees and 150 degrees, or between 140 degrees to 160degrees. In some embodiments, the heel-side taper angle β_(h) can beapproximately 120 degrees, 121 degrees, 122 degrees, 123 degrees, 124degrees, 125 degrees, 126 degrees, 127 degrees, 128 degrees, 129degrees, 130 degrees, 131 degrees, 132 degrees, 133 degrees, 134degrees, 135 degrees, 136 degrees, 137 degrees, 138 degrees, 139degrees, or 140 degrees. In many embodiments, the heel-side taper angleβ_(h) can be similar to the toe-side taper angle β_(t).

In many embodiments, the toe-side taper angle β_(t) can range betweenapproximately 100 degrees and approximately 160 degrees. In manyembodiments, the toe-side taper angle β_(t) can be between 100 degreesand 110 degrees, between 110 degrees and 120 degrees, between 120degrees and 130 degrees, between 130 degrees and 140 degrees, between140 degrees and 150 degrees, or between 150 degrees and 160 degrees. Inmany embodiments, the toe-side taper angle β_(t) can be between 110degrees and 130 degrees, between 115 degrees and 135 degrees, between120 degrees and 140 degrees, between 125 degrees and 145 degrees, orbetween 130 degrees and 150 degrees. In some embodiments, the toe-sidetaper angle can be approximately 120 degrees, 121 degrees, 122 degrees,123 degrees, 124 degrees, 125 degrees, 126 degrees, 127 degrees, 128degrees, 129 degrees, 130 degrees, 131 degrees, 132 degrees, 133degrees, 134 degrees, 135 degrees, 136 degrees, 137 degrees, 138degrees, 139 degrees, or 140 degrees.

The tapered shape of the sole return 154 provides space where the heelmass 147 and the toe mass 149 can concentrate mass within the lower heelareas and lower toe areas without contacting the sole return 154. Thetapering of the sole return 154 provides space for a greater amount ofmass to be allocated in the heel mass 147 and the toe mass 149 withoutcontacting the sole return 154. This configuration increases perimeterweighting of the club head 100 without interfering with the flexure ofthe faceplate 150.

In many embodiments, the sole return 154 can comprise a maximum solereturn width 157 ranging between approximately 1.5 inches andapproximately 3.0 inches. In some embodiments, the maximum sole returnwidth 157 can be between 1.5 inches and 2.5 inches, between 1.75 inchesand 2.75 inches, or between 2.0 inches and 3.0 inches. In someembodiments, the maximum sole return width 157 can be between 1.5 inchesand 2.0 inches, between 1.5 inches and 2.25 inches, between 1.5 inchesand 2.5 inches, between 1.5 inches and 2.75 inches, between 2.0 inchesand 2.25 inches, between 2.0 inches and 2.5 inches, between 2.0 inchesand 2.75 inches, or between 2.0 inches and 3.0 inches.

As discussed above, the sole return 154 further defines a sole returndepth 158 measured in a front-to-rear direction from the leading edge118 to the rear sole perimeter edge 166 c of the sole return 154. Inmany embodiments, as shown in FIG. 7 , the sole return depth 158 can besubstantially constant in a heel-to-toe direction. In other embodiments,the sole return depth 158 can vary from the heel end 106 to the toe end108. In some embodiments, the sole return 154 can comprise a maximumsole return depth 158 near a center of the sole return 154 (with respectto a heel-to-toe direction) and a minimum sole return depth 158 near theheel end 106 and/or the toe end 108.

In many embodiments, the sole return 154 can comprise a maximum solereturn depth 158 ranging between approximately 0.2 inch andapproximately 0.4 inch. In some embodiments, the maximum sole returndepth 158 can be between 0.2 inch and 0.4 inch or between 0.3 inch and0.4 inch. In some embodiments, the maximum sole return depth 158 can bebetween 0.2 inch and 0.25 inch, between 0.25 inch and 0.275 inch,between 0.275 inch and 0.3 inch, between 0.3 inch and 0.325 inch,between 0.325 inch and 0.35 inch, between 0.35 inch and 0.375 inch, orbetween 0.375 inch and 0.4 inch. In many embodiments, the maximum solereturn depth 158 can be greater than 0.2 inches. In some embodiments,the maximum sole return depth 158 can be greater than 0.2 inch, 0.225inch, 0.25 inch, 0.275 inch, 0.3 inch, 0.325 inch, 0.35 inch, or 0.375inch.

In many embodiments, the sole return depth 158 is increased as much asallowed by the manufacturing process used to form the faceplate 150. Inmany embodiments, the sole return depth 158 must be less thanapproximately 0.400 inch. In many embodiments, the faceplate 150 isformed by a machining and forming process. In such a process, the solereturn length 158 is limited by the forming tool. In many embodiments,the sole return depth 158 is as close to possible to the maximum depthallowed by the forming tool. Maximizing the sole return depth 158produces the greatest amount of flexure in the club head 100 andprovides the greatest increase in ball speed.

The flexure of the sole return 154 can depend on the amount of the solereturn 154 that is unhindered by other surfaces. For example, the depth158 along which the sole return 154 is unhindered can be considered an“effective” sole return depth, as the sole return 154 is free to flexalong the unhindered effective sole return depth. In some embodiments,where the golf club head 100 comprises a sole ledge 148, the sole return154 is unhindered by the weight pad 1000 or any other surface. In theseembodiments, the effective sole return depth, and the sole return depth158 are the same. For example, the club head 100 illustrated in FIG. 6and the club head 200 illustrated in FIG. 8 each comprise a sole ledge148, 248 making the effective sole return depth equal to the sole returndepth 158. In general, the greater the effective sole return depth, thegreater the sole return 154 is able to flex.

The sole perimeter edge 166 of the embodiment of FIG. 7 creates asubstantially trapezoidal shape for the sole return 154. In someembodiments, the sole return 154 can be formed in a variety of differentshapes. In many embodiments, the sole return 154 can be substantiallyrectangular. In other embodiments, from a sole view, the sole return 154can resemble a parallelogram, a polygon, a semicircle, a semi-ellipse, atriangle, or any other suitable shape.

It should be noted that in the examples illustrated at FIGS. 6 and 7 ,the sole return 154 significantly increases energy transfer at impact.The sole return 154 replaces a large amount of rear body material withfaceplate material, and the weld line on the sole 112 is moved fartherfrom the strike face 116 relative to a club head devoid of a solereturn. This increases flexure and therefore energy transfer on lowmis-hits (i.e., shots that are struck below the center of the face,closer to the sole). While similar prior art hollow body irons devoid ofsole returns experience a significant loss in ball speed on lowmis-hits, the club head 100 comprising the sole return 154 retains anincreased amount of ball speed on low mis-hits.

As mentioned above, the L-shaped faceplate 150 can be joined to the rearbody 130 via welding the faceplate perimeter edges to the weldingsurfaces 146 of the rear body 130. As illustrated in FIG. 4 , thefaceplate perimeter edges can be welded flat to the rear body 130 at thewelding surfaces 146, without any overlap between the rear body 130 andthe faceplate 150 and without any additional mechanical attachment orretention features. A plurality of weld lines can be formed between theL-shaped faceplate 150 and the rear body 130 at the interface betweenthe faceplate perimeter edges and the rear body welding surfaces 146.The plurality of weld lines can be formed at an outermost point of theinterface between the welding surfaces 146 and the perimeter edge (i.e.,on an external surface of the toe, the top rail, and/or the sole). Inmany embodiments, the plurality of weld lines is located at the clubhead peripheries 122, 124, 128 and away from the strike face 116 topromote flexure in the strike face 116. In many embodiments, thefaceplate 150 and the rear body 130 can be welded together via a laserwelding process. In alternative embodiments, the faceplate 150 and therear body 130 can be welded together via plasma welding, electron beamwelding, metal inert gas welding, or other welding processes.

In alternative embodiments, the faceplate 150 can optionally form anycombination of a top rail return, a toe return, and a sole return. Insuch embodiments, the top rail return and the toe return can each extendrearward from the strike face back surface 156 and form a significantportion of the top rail 110 or toe end 108, respectively. In suchembodiments, a greater amount of rear body material, particularly thatof the rear body top rail portion 132 and the rear body toe portion 136,can be replaced by faceplate material, and the weld line along the toprail 110 and the toe end 108 can be moved further from the strike face116. Providing a top rail return and/or a toe return can furtherincrease flexure in the club head 100 and provide higher ball speeds.

B. L-Shaped Faceplate without Top Rail Extension and Toe Extension

In some embodiments, the perimeter of the L-shaped faceplate may bedevoid of a toe extension and/or heel extension and may not extend allthe way to the club head periphery on the toe end and/or the top rail.FIGS. 8 and 9 illustrate a second embodiment of a hollow-body iron-typeclub head 200 comprising an L-shaped faceplate 250 without a toeextension or a top rail extension. The second embodiment of the clubhead 200 is substantially similar to club head 100, but for thedifference in faceplate shape. Club head 200 can comprise similarfeatures to club head 100, labeled with a 200 numbering scheme (i.e.,club head 200 comprises a rear body 230, a faceplate 250, etc.).

The L-shaped faceplate 250 of club head 200 is devoid of toe extensionand a top rail extension and thus comprises perimeter edges 260, 262,264 that do not extend to the club head peripheries 222, 224, 226. TheL-shaped faceplate 250 devoid of a toe extension and a top railextension can be combined with any rear body 230 geometry or featuredescribed either above or below, including a sole ledge 248, an angledweight pad 1000, a weight pad 2000 comprising an extension 2050, a heelmass 247 and/or toe mass 249, a lower interior undercut 290, an upperinterior undercut 295, a rear exterior cavity 298, an external flexurehinge 3000, an internal bending notch 3100, an internal welding rib 279,or any combination thereof.

As shown in FIG. 8 , the toe side perimeter edge 264 is locatedproximate the toe end 208, but on the strike face 216. As such, thefaceplate 250 does not form a toe extension. Near the toe end 208, thefaceplate 250 is confined to the strike face 216. The faceplate does notform any portion of the toe end 208, and the toe side perimeter edge 264is not located on the toe side periphery 224. Similarly, the topperimeter edge 260 is located proximate the top rail 210, but on thestrike face 216. As such, the faceplate 250 does not form a top railextension. Near the top rail 210, the faceplate 250 is confined to thestrike face 216. The faceplate 250 does not form any portion of the toprail 210, and the top perimeter edge 260 is not located on the top railperiphery 226.

Due to the lack of the top rail extension and the toe extension, therear body 230 of club head 200 forms the entirety of the club headperipheries 222, 224, 226, apart from the sole periphery 228, whichcomprises the faceplate sole return 254. Referring to FIG. 9 , the rearbody 230 forms the entire top rail 210, the entire toe end 208, and theentire heel end 206 (including the hosel structure). The L-shapedfaceplate 250 of club head 200 is confined to the strike face 216, withthe exception of the sole return 254, which wraps over the leading edge218 and forms a portion of the sole 212.

Similar to club head 100, the L-shaped faceplate 250 increases theamount of flexure occurring in the club head 200 at impact, resulting inhigher ball speeds. The sole return 254 replaces portions of the sole212 that would otherwise be formed by the rear body 230 withhigh-strength faceplate material. The sole return 254 allows the strikeface 216 and the sole 212 to have reduced thicknesses withoutsacrificing durability by using a faceplate material with increasedstrength located at high stress regions (i.e., the portion of the sole212 proximate the leading edge 118). The sole return 254 also increasesthe flexibility of the faceplate 250 by moving the bottom weld line tothe sole 212 and off the strike face 216. The L-shaped faceplate 250increases energy transfer between the strike face 216 and the golf ballat impact by increasing the flexibility of the faceplate 250. The clubhead comprising an L-shaped faceplate 250 produces higher ball speeds incomparison to a similar club head devoid of a similar faceplate.

II. Overhanging Weight Pad

In many embodiments, the rear body 130 can comprise a weight pad 1000formed in the interior cavity 114 that forms an overhang extending overa portion of the sole 112 and/or a portion of the sole return 154, asillustrated in FIGS. 10 and 11 . A portion of the weight pad 1000 canoverhang the sole 112, without contacting the faceplate 150, in order toprovide a club head 100 with a low CG without sacrificing theflexibility of the L-shaped faceplate 150. The weight pad 1000 comprisesa mass of rear body 130 material extending upward from the sole 112 intothe interior cavity 114 and located proximate the rear wall 140. Theweight pad 1000 can be formed integrally with both the rear body soleportion 138 and the rear wall 140. The weight pad 1000 locates a greaterportion of mass towards the sole 112, driving the CG position of theclub head 100 lower, while allowing space for the faceplate 150 todeflect. The weight pad 1000 can extend from the heel end 106 of theinterior cavity 114 to the toe end 108. The weight pad 1000 can comprisea front wall 1010 facing the front end 102 of the club head 100, a topwall 1020 facing the top rail 110, and a transition region 1030 betweenthe front wall 1010 and the top wall 1020. In many embodiments, thetransition region 1030 can be rounded off to provide a smooth transitionbetween the top wall 1020 and the front wall 1010, as illustrated inFIG. 11 .

The front wall 1010 of the weight pad 1000 forms a juncture with thesole ledge 148 near the sole 112. The weight pad 1000 is locatedrearward of the faceplate 150 and is separated from the faceplate 150 bythe sole ledge 148. The sole ledge depth 153 is selected to provide abuffer region between the weight pad 1000 and the faceplate 150, whilestill allowing the weight pad 1000 to overhang the faceplate 150.

As discussed in further detail below, the weight pad 1000 forms a lowerinterior undercut 190 between a lower and/or forward surface of theweight pad 1000 and the sole 112. The lower interior undercut 190 allowsadditional mass to be added to the weight pad 1000 to lower the clubhead CG position without interfering with the flexure of the faceplate150. The lower interior undercut 190 further serves to provide stressrelief within thin portions of the sole 112 (i.e., the sole ledge 148and sole return 154), by effectively lengthening said thin portions.

In some embodiments, the club head can comprise a CG height 109 between0.425 inch to 0.650 inch. In some embodiments, the CG height 109 can bebetween 0.425 inch to 0.450 inch, between 0.450 inch to 0.475 inch,between 0.475 inch to 0.500 inch, between 0.500 inch to 0.525 inch,between 0.525 inch to 0.550 inch, between 0.550 inch to 0.575 inch,between 0.575 inch to 0.600 inch, between 0.600 inch to 0.625 inch, orbetween 0.625 inch to 0.650 inch. In some embodiments, the CG height isless than 0.650 inch, less than 0.600 inch, less than 0.550 inch, lessthan 0.500 inch, less than 0.450 inch, or less than 0.400 inch.

In some embodiments, referring to FIGS. 10 and 11 , the weight pad frontwall 1010 can be angled with respect to the sole 112. In manyembodiments, the weight pad front wall 1010 forms an acute angle α withthe sole return interior surface 161 such that a portion of the weightpad 1000 overhangs a portion of the sole return 154, as illustrated inFIG. 11 . Due to the angled nature of the weight pad 1000, the frontwall 1010 extends upward from the sole 112 and toward the faceplate 150.In many embodiments, the transition region 1030 can form a forwardmostportion of the weight pad 1000, as the transition region 1030 is locatedat the top of the front wall 1010.

In some embodiments, the angle α between the weight pad front wall 1010and the sole return interior surface 161 can be between approximately 30degrees and approximately 80 degrees. In some embodiments, the angle αcan be between 30 and 35 degrees, 35 and 40 degrees, 40 and 45 degrees,45 and 50 degrees, 50 and 55 degrees, 55 and 60 degrees, 60 and 65degrees, 65 and 70 degrees, 70 and 75 degrees, or 75 and 80 degrees. Theangle α can be selected to allow the weight pad 1000 to projectsubstantially forward toward the faceplate 150. The steeper the angle α,the more forward and lower the weight pad 1000 can protrude, whichlowers the CG of the club head 100.

The angled weight pad 1000 provides multiple performance benefits over aweight pad devoid of an angled front wall 1010. Angling the front wall1010 allows a portion of the weight pad 1000 to overhang a portion ofthe sole return 154. By overhanging the sole return 154, the weight pad1000 concentrates a large amount of mass low in the club head 100without contacting the sole return 154. This arrangement lowers the clubhead CG without interfering with the flexure of the faceplate 150. Thecombination of a low CG and high flexibility in the club head 100 createperformance improvements such as increased ball speed and increasedlaunch angle.

Referring to FIG. 11 , the amount the angled weight pad 1000 overhangsthe sole return 154 can be characterized by an overhang distance 1090.The overhang distance 1090 can be measured as the horizontal distancebetween the weight pad transition region 1030 and the sole perimeteredge 166. The greater the overhang distance 1090, the greater the amountof mass that can be placed low in the club head 100 without contactingthe sole return 154, thus lowering the CG without prohibiting flexure.The overhang distance 1090 can be greater than approximately 0.025 inch,greater than approximately 0.05 inch, greater than approximately 0.075inch, greater than approximately 0.100 inch, greater than approximately0.125 inch, greater than approximately 0.150 inch, greater thanapproximately 0.175 inch, or greater than approximately 0.200 inch. Insome embodiments, the overhang distance 1090 can be between 0.025 inchto 0.075 inch, 0.040 inch to 0.060 inch, 0.075 inch to 0.100 inch, 0.090inch to 0.125 inch, 0.120 inch to 0.175 inch, 0.150 inch to 0.200 inch,or 0.175 inch to 0.300 inch. In one exemplary embodiment, the overhangdistance 1090 is approximately 0.05 inch. The overhang distance 1090 isselected to allow the faceplate 150 to flex without contacting theweight pad 2000.

The weight pad front wall 1010 is angled forward such that a lowerinterior undercut 190 can be formed between the angled weight pad frontwall 1010 and the sole 112. As best shown in FIG. 11 , the lowerinterior undercut 190 is defined as the volume underneath the weight padfront wall 1010 and above the sole return 154 and the sole ledge 148.The lower interior undercut 190 separates the thin sole portion from theweight pad 2000. Referring to FIG. 11 , the lower interior undercut 190can define a lower interior undercut depth 192 and a lower interiorundercut height 191. The lower interior undercut depth 192 is measuredas a front-to-rear distance between the weight pad transition region1030 and the juncture between the front wall 1010 and the sole ledge 148(which defines a rearmost point of the lower interior undercut). Thelower interior undercut height 191 is defined as the vertical distancebetween the weight pad front wall 1010 and the sole return interiorsurface 161.

Referring to FIG. 11 , the lower interior undercut depth 192, measuredbetween the weight pad transition region 1030 and the juncture betweenthe front wall 1010 and the sole ledge 148, has a range of 0.010 inch to0.300 inch. For example, the lower interior undercut depth 192 can rangefrom 0.010 inch to 0.030 inch, 0.030 inch to 0.050 inch, 0.050 inch to0.070 inch, 0.070 inch to 0.090 inch, 0.090 inch to 0.110 inch, 0.110inch to 0.130 inch, 0.130 inch to 0.150 inch, 0.150 inch to 0.170 inch,0.170 inch to 0.190 inch, 0.190 inch to 0.210 inch, 0.210 inch to 0.230inch, 0.230 inch to 0.250 inch, 0.250 inch to 0.270 inch, 0.270 inch to0.290 inch, or 0.290 inch to 0.300 inch. The lower interior undercutdepth 192 can be greater than approximately 0.010 inch, greater thanapproximately 0.015 inch, greater than approximately 0.020 inch, greaterthan approximately 0.025 inch greater than approximately 0.05 inch,greater than approximately 0.075 inch, greater than approximately 0.100inch, greater than approximately 0.125 inch, greater than approximately0.150 inch, greater than approximately 0.175 inch, or greater thanapproximately 0.200 inch. In one exemplary embodiment, the lowerinterior undercut depth 192 is approximately 0.140 inch.

Referring again to FIG. 11 , the lower interior undercut height 191,measured between the front wall 1010 and the sole return interiorsurface 161, can range from approximately 0.030 inch to approximately0.400 inch. For example, the lower interior undercut height 191 canrange from 0.030 inch to 0.050 inch, 0.050 inch to 0.070 inch, 0.070inch to 0.090 inch, 0.090 inch to 0.110 inch, 0.110 to 0.130 inch, 0.130inch to 0.150 inch, 0.150 inch to 0.170 inch, 0.170 inch to 0.190 inch,0.190 inch to 0.210 inch, 0.210 to 0.230 inch, 0.230 inch to 0.250 inch,0.250 inch to 0.270 inch, 0.270 inch to 0.290 inch, 0.290 inch to 0.310inch, 0.310 to 0.330 inch, 0.330 inch to 0.350 inch, 0.350 inch to 0.370inch, 0.370 inch to 0.390 inch, or 0.390 inch to 0.400 inch. The lowerinterior undercut height 191 can be greater than approximately 0.010inch, greater than approximately 0.015 inch, greater than approximately0.020 inch, greater than approximately 0.025 inch, greater thanapproximately 0.05 inch, greater than approximately 0.075 inch, greaterthan approximately 0.100 inch, greater than approximately 0.125 inch,greater than approximately 0.150 inch, greater than approximately 0.175inch, greater than approximately 0.200 inch, greater than approximately0.225 inch, greater than approximately 0.250 inch, greater thanapproximately 0.275 inch, greater than approximately 0.300 inch, greaterthan approximately 0.325 inch, greater than approximately 0.350 inch, orgreater than approximately 0.375 inch. In one exemplary embodiment, thelower interior undercut height 191 is approximately 0.340 inch.

The lower interior undercut 190 can be considered as a region of theweight pad 1000 that has been removed, when compared to iron-type golfclub heads lacking an undercut. The lower interior undercut 190 allowsthin portions of the sole 112 to be extended. The lower interiorundercut 190 can allow for a decrease in the peak stress experiencedwithin the thin portions of the sole 112 and an increase in theflexibility of the sole 112. Rather than behaving as a rigid connection,the lower interior undercut 190 generates stress relief at the face-soletransition by allowing the sole return 154 and the sole ledge 148 todeflect to a greater extent under impact loads. The lower interiorundercut's 190 effective increase in the length of the sole return 154and/or the sole ledge 148 increases the total surface area over whichimpact load is distributed, creating a reduction in peak stress withinthe sole ledge 148 and sole return. The lower interior undercut 190dually reduces stress concentrations within the sole ledge 148 and thesole return 154 and increases the bending/spring effect of the sole 112.

In another embodiment, as illustrated in FIG. 12 , rather than beingangled with respect to the sole 112, the weight pad 2000 forms a weightpad extension 2050 protruding forward from the weight pad 2000 towardthe faceplate 150 and overhanging the sole return 154 and the sole ledge148. The overhang of the weight pad 2000 over the sole return 154 andsole ledge 148 forms a lower interior undercut 190, as discussed infurther detail below. The weight pad 2000 comprising a weight padextension 2050 and a lower interior undercut 190 allows a large amountof mass to be positioned low in the club head 100 without interferingwith the flexure of the faceplate 150.

Referring to FIG. 13 , the weight pad extension 2050 can protrude fromthe front wall 2010 of the weight pad 2000 and extend approximatelyparallel to the sole 112. The weight pad extension 2050 protrudesforward through the interior cavity 114 toward the strike face backsurface 156. The weight pad extension 2050 comprises a forward edge 2060defining the forwardmost extent of the weight pad extension 2050. Theweight pad extension 2050 does not contact the strike face back surface156. The forward edge 2060 of the weight pad extension 2050 is spacedaway from the strike face back surface 156 so as not to interfere withthe flexure of the faceplate 150 at impact.

The spacing between the weight pad extension 2050 and the faceplate 150can be characterized by a horizontal offset distance 2080 measuredbetween the strike face back surface 156 and the forward edge 2060 ofthe weight pad extension 2050. The horizontal offset distance 2080 canbe as small as possible while still allowing sufficient space for thestrike face 116 to flex at impact. It is desirable for the weight padextension 2050 to extend as near to the strike face back surface 156 aspossible without interfering with the flexure of the faceplate 150. Thesmaller the horizontal offset distance 2080 between the strike face backsurface 156 and the forward edge 2060 of the weight pad extension 2050,the greater the amount of mass that can be allocated low in the clubhead 100.

In many embodiments, the horizontal offset distance 2080 between strikeface back surface 156 and the forward edge 2060 of the weight padextension 2050 can be less than approximately 0.30 inch. In someembodiments, the horizontal offset distance 2080 can be less thanapproximately 0.275 inch, less than approximately 0.25 inch, less thanapproximately 0.225 inch, less than approximately 0.20 inch, less thanapproximately 0.175 inch, less than approximately 0.15 inch, less thanapproximately 0.125 inch, less than approximately 0.10 inch, less thanapproximately 0.075 inch, or less than approximately 0.05 inch. Thehorizontal offset distance 2080 is selected to allow the faceplate 150to deflect without contacting the weight pad 2000.

As mentioned above, the weight pad extension 2050 overhangs both thesole ledge 148 and the sole return 154. The overhang of the weight padextension 2050 creates a lower interior undercut 190 that allows themass of the weight pad 2000 to be placed low and forward withoutcontacting the sole return 154 or interfering with the flexure of thefaceplate 150.

The weight pad extension 2050 overhangs the sole return 154, allowingthe weight pad 2000 to lower the club head CG position withoutcontacting the sole return 154 and prohibiting the faceplate 150 fromflexing. The amount of overhang can be characterized by an overhangdistance 2090 measured between the weight pad extension forward edge2060 and the sole perimeter edge 166. The greater the overhang distance2090, the shorter the weight pad 2000 can be without contacting the solereturn 154, thus lowering the CG without prohibiting flexure. Theoverhang distance 2090 greater than approximately 0.050 inch, greaterthan approximately 0.075 inch, greater than approximately 0.100 inch,greater than approximately 0.125 inch, greater than approximately 0.150inch, greater than approximately 0.175 inch, or greater thanapproximately 0.200 inch. In some embodiments, the overhang distance2090 can be between 0.050 inch to 0.075 inch, 0.020 inch to 0.060 inch,0.075 inch to 0.100 inch, 0.090 inch to 0.125 inch, 0.120 inch to 0.175inch, 0.150 inch to 0.200 inch, or 0.175 inch to 0.300 inch. In oneexemplary embodiment, the overhang distance 2090 is approximately 0.250inch. The overhang distance 2090 is selected to allow the faceplate 150to deflect without contacting the weight pad 2000.

In many embodiments, as illustrated by FIG. 13 , the weight padextension 2050 comprises a lower surface 2070 disposed toward the sole112. The weight pad extension lower surface 2070 can be offsetvertically from the sole return interior surface 161 such that theweight pad extension 2050 does not contact the sole return 154. Thevertical offset between the weight pad extension lower surface 2070 andthe sole return interior surface 161 forms a lower interior undercut190. The lower interior undercut 190 is defined as the volume underneaththe weight pad extension 2050 and above the sole 112. The lower interiorundercut 190 is bounded by the front wall 2010 of the weight pad 2000,the lower surface 2070 of the weight pad extension 2050, the sole ledge148, and the sole return interior surface 161. The lower interiorundercut 190 extends laterally in a heel to toe direction over a heel totoe length of the weight pad 2000. The weight pad extension 2050 candefine a first plane 2065 extending along the forward edge 2060 of theweight pad extension 2050 and intersecting the sole 112. A lowerinterior undercut opening can be defined between the weight padextension 2050 and the sole at the first plane 2065. The lower interiorundercut 190 can define a lower interior undercut depth 192 and a lowerinterior undercut height 191. The lower interior undercut depth 192 ismeasured as a perpendicular distance between the first plane 2065 andthe front wall of the weight pad (which defines a rearmost point of thelower interior undercut 190). The lower interior undercut height 191 isdefined as the vertical distance between the weight pad extension lowersurface 2070 and the sole return interior surface 161.

Referring to FIG. 13 , the lower interior undercut depth 192, betweenthe first plane 2065 and the sole return interior surface 161 can bebetween approximately 0.010 inch to approximately 0.300 inch. Forexample, the lower interior undercut depth 192 can range from 0.010 inchto 0.030 inch, 0.030 inch to 0.050 inch, 0.050 inch to 0.070 inch, 0.070inch to 0.090 inch, 0.090 inch to 0.110 inch, 0.110 inch to 0.130 inch,0.130 inch to 0.150 inch, 0.150 inch to 0.170 inch, 0.170 inch to 0.190inch, 0.190 inch to 0.210 inch, 0.210 inch to 0.230 inch, 0.230 inch to0.250 inch, 0.250 inch to 0.270 inch, 0.270 inch to 0.290 inch, or 0.290inch to 0.300 inch. The lower interior undercut depth 192 can be greaterthan approximately 0.010 inch, greater than approximately 0.015 inch,greater than approximately 0.020 inch, greater than approximately 0.025inch greater than approximately 0.05 inch, greater than approximately0.075 inch, greater than approximately 0.100 inch, greater thanapproximately 0.125 inch, greater than approximately 0.150 inch, greaterthan approximately 0.175 inch, greater than approximately 0.200 inch,greater than approximately 0.225 inch, greater than approximately 0.250inch, or greater than approximately 0.275 inch. In one exemplaryembodiment, the lower interior undercut depth 192 is approximately 0.140inch.

Referring again to FIG. 13 , the lower interior undercut height 191,measured between the weight pad extension lower surface 2070 and thesole return interior surface 161, can range from approximately 0.030inch to approximately 0.200 inch. For example, the lower interiorundercut height 191 can range from 0.030 inch to 0.040 inch, 0.040 inchto 0.050 inch, 0.050 inch to 0.060 inch, 0.060 inch to 0.070 inch, 0.070inch to 0.080 inch, 0.080 inch to 0.090 inch, 0.090 inch to 0.100 inch,0.100 inch to 0.110 inch, 0.110 to 0.120 inch, 0.120 inch to 0.130 inch,0.130 inch to 0.140 inch, 0.140 inch to 0.150 inch, 0.150 inch to 0.160inch, 0.160 inch to 0.170 inch, 0.170 inch to 0.180 inch, 0.180 inch to0.190 inch, or 0.190 inch to 0.200 inch. The lower interior undercutheight 191 can be greater than approximately 0.010 inch, greater thanapproximately 0.015 inch, greater than approximately 0.020 inch, greaterthan approximately 0.025 inch, greater than approximately 0.05 inch,greater than approximately 0.075 inch, greater than approximately 0.100inch, greater than approximately 0.125 inch, greater than approximately0.150 inch, or greater than approximately 0.175 inch.

The overhanging weight pads 1000, 2000 described above can be combinedwith any of the various L-shaped faceplate 150 geometries describedabove including a sole return 154, a toe extension 168, a top railextension 170, or any combination thereof. The overhanging weight pads1000, 2000 described above can also be combined with rear body 130geometry or feature described either above or below, including a soleledge 148, a heel mass 147 and/or toe mass 149, a lower interiorundercut 190, an upper interior undercut 195, a rear exterior cavity198, an external flexure hinge 3000, an internal bending notch 3100, aninternal welding rib 179, or any combination thereof. Similarly, thelower interior undercut 190 can be combined with any faceplate 150geometry described above, any rear body 130 geometry or featuredescribed above or below, or any combination thereof.

A. Overhanging Weight Pad Continuous with Rear Wall Interior Surface

FIGS. 25-28 disclose embodiments of club heads having weight pads thatare continuous with a rear wall upper portion 480. There are nocavities, transitions, or other recesses interposed between the weightpad 4000 and the rear wall upper portion 480 in these embodiments ofFIGS. 25-28 . The weight pad 4000 is formed within a portion of the rearbody 430 positioned below the rear wall upper portion 480 (referred toas the rear wall lower portion). The weight pad 4000 includes a forwardedge 477 that extends continuously from the rear wall upper portioninterior surface 459. The forward edge 477 includes an upper region 467and a lower region 469 and is spaced from the strike face back surface456. A lower interior undercut 490 extends rearwardly from the forwardedge 477 and between the weight pad 4000 and the sole ledge 448. Thelower interior undercut 490 defines a gap between the weight pad 4000and the sole return 454. The rear body 430 includes an exterior surfacethat can comprise a shelf surface 443 that boarders an upper end of theweight pad 4000. Additionally, a back face 440 can boarder the back endof the weight pad 4000 to create the rear body exterior geometry withthe shelf surface 443.

Referring to FIGS. 25-28 , an embodiment of the club head 400 cancomprise a weight pad 4000 in the rear body 430 that is continuous witha rear wall upper portion 480. The weight pad 4000 is formed between arear wall lower portion exterior surface 473 and a rear wall lowerportion interior surface 445, positioning the weight pad 4000 proximatethe sole 412. The rear wall upper portion interior surface 459 lies in afirst plane 420 and at least the upper region 467 of the weight padforward edge 477 lies in a second plane 421. In the exemplary embodimentillustrated in FIGS. 25-28 , the first and second planes 420, 421 areco-planar. In this embodiment, the lower region 469 of the weight padforward edge 477 can lie in the second plane 421 with the upper region467. The first and second planes 420, 421 are additionally parallel tothe loft plane 401.

The rear wall interior surface 439 comprises an upper and lower portion459, 445 that corresponds with the upper and lower portions 480, 431 ofthe rear wall. The rear wall upper portion interior surface 459continuously transitions into the weight pad forward edge 477. The rearwall lower portion is congruent with the forward edge 477 of the weightpad 4000. A portion of the weight pad 4000 can overhang the sole return454, without contacting the faceplate 450. The weight pad 4000 locates agreater portion of mass toward the sole 412 of the club head 400,driving the CG position of the club head 400 lower, as described abovewith a CG height between 0.425 inch to 0.650 inch, while allowing spacefor the faceplate 450 to flex during impact with a golf ball.

Referring to FIGS. 25-27 , the rear wall upper portion 480 can becomprised of a rear wall upper portion interior surface 459 and a rearwall upper portion exterior surface 455. The thickness of the rear wallupper portion 480 can be measured between the rear wall upper portioninterior surface 459 and a rear wall upper portion exterior surface 455.The rear wall upper portion thickness 435 can be minimized to push moremass downward and forward, lowering the CG, while still allowing theL-shaped faceplate 450 and the sole 412 to flex. A thin rear wall upperportion 480 can also allow the body of the club head 400 to flex more.The rear wall upper portion thickness 435 can be held constant acrossthe entirety of the rear wall upper portion 480. In some embodiments,the rear wall upper portion thickness 435 can be between 0.025 inches to0.070 inches. In some embodiments, the rear wall upper portion thickness435 can be between 0.025 inches and 0.030 inches, between 0.025 inchesand 0.035 inches, or between 0.025 inches and 0.040 inches. In someembodiments, the rear wall upper portion thickness 435 can be less thanapproximately 0.070 inch, less than approximately 0.065 inch, less thanapproximately 0.060 inch, less than approximately 0.055 inch, less thanapproximately 0.050 inch, less than approximately 0.045 inch, less thanapproximately 0.040 inch, less than approximately 0.035 inch, less thanapproximately 0.030 inch, or less than approximately 0.025 inch. Therear wall upper portion thickness 435 can be between 0.025 inch to 0.050inch, 0.035 inch to 0.050 inch, 0.040 inch to 0.065 inch, or 0.045 inchto 0.070 inch. In one exemplary embodiment, the rear wall upper portionthickness 435 is approximately 0.032 inches.

Further, the rear wall upper portion interior surface 459 is in a firstplane 420 and the rear wall lower portion interior surface 445 is in asecond plane 421. As shown in FIG. 27 , the first plane 420 and secondplane 421 are co-planar. Thus, the entirety of the rear wall interiorsurface 439 is within the same plane. Since the forward edge 477 of theweight pad 4000 is congruent with the rear wall lower portion interiorsurface 445, the forward edge 477 of the weight pad 4000 is also withinthe second plane 421 and co-planar with the first plane 420. The firstplane 420 and second plane 421 can be parallel to the loft plane 401,thus the rear wall upper portion interior surface 459 and the forwardedge 477 of the weight pad 4000 are parallel to the loft plane 401. Inthis embodiments, the upper and lower regions 467, 469 of the weight padforward edge 477 lie in the second plane 421.

In some embodiments, the first plane 420 can be offset in aperpendicular direction from the loft plane 401 at a distance between0.200 inches and 0.300 inches. In some embodiments, the first plane 420can be offset from the loft plane 401 between 0.200 inches and 0.205inches, 0.205 inches and 0.210 inches, 0.210 inches and 0.215 inches,0.215 inches and 0.220 inches, 0.220 inches and 0.225 inches, 0.225inches and 0.230 inches, 0.230 inches and 0.235 inches, 0.235 inches and0.240 inches, 0.240 inches and 0.245 inches, 0.245 inches and 0.250inches, 0.250 inches and 0.255 inches, 0.255 inches and 0.260 inches,0.260 inches and 0.265 inches, 0.265 inches and 0.270 inches, 0.270inches and 0.275 inches, 0.275 inches and 0.280 inches, 0.280 inches and0.285 inches, 0.285 inches and 0.290 inches, 0.290 inches and 0.295inches, or 0.295 inches and 0.300 inches. In one exemplary embodiment,the first plane 420 is offset from the loft plane 401 at a distance of0.250 inches.

In some embodiments, the second plane 421 can be offset in aperpendicular direction from the loft plane 401 at a distance between0.200 inches to 0.300 inches. In some embodiments, the second plane 421can be offset from the loft plane 401 between 0.200 inches and 0.205inches, 0.205 inches and 0.210 inches, 0.210 inches and 0.215 inches,0.215 inches and 0.220 inches, 0.220 inches and 0.225 inches, 0.225inches and 0.230 inches, 0.230 inches and 0.235 inches, 0.235 inches and0.240 inches, 0.240 inches and 0.245 inches, 0.245 inches and 0.250inches, 0.250 inches and 0.255 inches, 0.255 inches and 0.260 inches,0.260 inches and 0.265 inches, 0.265 inches and 0.270 inches, 0.270inches and 0.275 inches, 0.275 inches and 0.280 inches, 0.280 inches and0.285 inches, 0.285 inches and 0.290 inches, 0.290 inches and 0.295inches, or 0.295 inches and 0.300 inches. In one exemplary embodiment,the second plane 421 is offset from the loft plane 401 at a distance of0.250 inches.

In some embodiments, the rear wall interior surface 439 can be offset ina perpendicular direction from the loft plane 401 at a distance between0.200 inches to 0.300 inches. In some embodiments, the rear wallinterior surface 439 can be offset from the loft plane 401 between 0.200inches and 0.205 inches, 0.205 inches and 0.210 inches, 0.210 inches and0.215 inches, 0.215 inches and 0.220 inches, 0.220 inches and 0.225inches, 0.225 inches and 0.230 inches, 0.230 inches and 0.235 inches,0.235 inches and 0.240 inches, 0.240 inches and 0.245 inches, 0.245inches and 0.250 inches, 0.250 inches and 0.255 inches, 0.255 inches and0.260 inches, 0.260 inches and 0.265 inches, 0.265 inches and 0.270inches, 0.270 inches and 0.275 inches, 0.275 inches and 0.280 inches,0.280 inches and 0.285 inches, 0.285 inches and 0.290 inches, 0.290inches and 0.295 inches, or 0.295 inches and 0.300 inches. In oneexemplary embodiment, the rear wall interior surface 439 is offset fromthe loft plane 401 at a distance of 0.250 inches.

In some embodiments, the weight pad forward edge 477 can be offset in aperpendicular direction from the loft plane 401 at a distance between0.200 inches to 0.300 inches. In some embodiments, the weight padforward edge 477 can be offset from the loft plane 401 between 0.200inches and 0.205 inches, 0.205 inches and 0.210 inches, 0.210 inches and0.215 inches, 0.215 inches and 0.220 inches, 0.220 inches and 0.225inches, 0.225 inches and 0.230 inches, 0.230 inches and 0.235 inches,0.235 inches and 0.240 inches, 0.240 inches and 0.245 inches, 0.245inches and 0.250 inches, 0.250 inches and 0.255 inches, 0.255 inches and0.260 inches, 0.260 inches and 0.265 inches, 0.265 inches and 0.270inches, 0.270 inches and 0.275 inches, 0.275 inches and 0.280 inches,0.280 inches and 0.285 inches, 0.285 inches and 0.290 inches, 0.290inches and 0.295 inches, or 0.295 inches and 0.300 inches. In oneexemplary embodiment, the weight pad forward edge 477 is offset from theloft plane 401 at a distance of 0.250 inches.

Referring to FIG. 25 , a lower interior undercut 490 is between theweight pad 4000 and the sole ledge 448. The lower interior undercut 490extends rearwardly from the weight pad forward edge 477 and defines agap between the weight pad 4000 and the sole return 454. As shown inFIG. 25 , the lower interior undercut 490 additionally defines a volumeunderneath the weight pad 4000 and above the sole return 454 and soleledge 448. Referring to FIG. 28 , the lower interior undercut 490 candefine a lower interior undercut depth 492 and a lower interior undercutheight 491. The lower interior undercut depth 492 is measured as afront-to-rear distance between the forwardmost point of weight pad 4000and the rearmost point of the lower interior undercut 490. In someembodiments, the lower interior undercut depth 492 can be between 0.225inch and 0.275 inch. In some examples, the lower interior undercut depth492 can be between 0.225 inch and 0.230 inch, 0.230 inch and 0.235 inch,0.235 inch and 0.240 inch, 0.240 inch and 0.245 inch, 0.245 inch and0.250 inch, 0.250 inch and 0.255 inch, 0.255 and 0.260 inch, 0.260 inchand 0.265 inch, 0.265 inch and 0.270 inch, or 0.270 inch and 0.275 inch.In one exemplary embodiment, the lower interior undercut depth 492 is0.250 inch. The lower interior undercut height 491 is defined as thevertical distance between a lower surface 465 and a sole return interiorsurface 419. In some embodiments, the lower interior undercut height 491can be between 0.140 inch and 0.190 inch. In some examples, the lowerinterior undercut height 491 can be between 0.140 inch and 0.145 inch,0.145 inch to 0.150 inch, 0.150 inch and 0.155 inch, 0.155 inch to 0.160inch, 0.160 inch and 0.165 inch, 0.165 inch to 0.170 inch, 0.170 inchand 0.175 inch, 0.175 inch to 0.180 inch, 0.180 inch and 0.185 inch, or0.185 inch to 0.190 inch. In one exemplary embodiment, the lowerinterior undercut height 491 is 0.162 inch.

In some embodiments, the volume of the internal cavity can be between0.555 in³ and 0.955 in³. In some embodiments, the volume of the internalcavity can be between 0.555 in³ and 0.600 in³, 0.600 in³ and 0.655 in³,0.655 in³ and 0.700 in³, 0.700 in³ and 0.755 in³, 0.755 in³ and 0.800in³, 0.800 in³ and 0.855 in³, 0.855 in³ and 0.900 in³, or 0.900 in³ and0.955 in³. In one exemplary embodiment, the volume of the internalcavity can be 0.772 in³.

As described above, the rear wall interior surface 439 comprises anupper and lower portion 459, 445 that corresponds with the upper andlower portions of the rear wall. In some embodiments, the rear wallupper portion interior surface 459 can cover between 55% and 65% of therear wall interior surface 439. In some embodiments, the rear wall upperportion interior surface 459 can cover between 55% to 57%, 57% to 59%,59% to 61%, 61% to 63%, or 63% to 65% of the rear wall interior surface439. In one exemplary embodiment, the rear wall upper portion interiorsurface 459 can cover 60% of the rear wall interior surface 439. In someembodiments, the rear wall lower portion interior surface 445 can coverbetween 30% and 50% of the rear wall interior surface 439. In someembodiments, the rear wall lower portion interior surface 445 can coverbetween 30% and 32%, 32% and 34%, 34% and 36%, 36% and 38%, 38% and 40%,40% and 42%, 42% and 44%, 44% and 46%, 46% and 48%, or 48% and 50% ofthe rear wall interior surface 439. In one exemplary embodiment, therear wall lower portion interior surface 445 can cover 40% of the rearwall interior surface 439. In some embodiments, the weight pad forwardedge 477 can cover between 30% and 32%, 32% and 34%, 34% and 36%, 36%and 38%, 38% and 40%, 40% and 42%, 42% and 44%, 44% and 46%, 46% and48%, or 48% and 50% of the rear wall interior surface 439. In oneexemplary embodiment, the weight pad forward edge 477 can cover 40% ofthe rear wall interior surface 439.

Referring to FIG. 26 , the rear wall lower portion exterior surface 473can comprise a shelf surface 443 that boarders an upper end of theweight pad 4000. The shelf surface 443 can extend substantiallyperpendicular (within 15° of perpendicular) to the rear wall upperportion exterior surface 455. The rear wall lower portion exteriorsurface 473 can comprise a back face 440 bordering a back end of theweight pad 4000. The back face 440 can extend between the shelf surface443 and the rear body sole portion 438.

B. Overhanging Weight Pad Continuous with and Off-Set from Rear WallInterior Surface

FIGS. 29-33 disclose embodiments of club heads having weight pads thatare continuous with a rear wall upper portion 480. There are no cavitiesor recesses interposed between the weight pad and the rear wall upperportion 480, however at least one transition can exist to create anoff-set weight pad 4000 relative to the rear wall upper portion interiorsurface 459. The rear wall upper portion interior surface 459 lies in afirst plane 420 and at least the upper region 467 of the weight padforward edge 477 lies in a second plane 421 wherein the first and secondplanes 420, 421 intersect. The first plane 420 is parallel to the loftplane 401 while the second plane 421 intersects the loft plane 401. Asdetailed above, a portion of the weight pad 4000 can overhang the solereturn 454, without contacting the faceplate 450. The weight pad 4000allocates a greater portion of mass towards the sole 412 of the golfclub head 400, driving the CG position of the club head 400 lower, asdescribed above with a CG height between 0.425 inch to 0.650 inch, whileallowing space for the faceplate 450 to deflect.

As described above, the rear wall can contain a rear wall upper portion480. In some embodiments, the rear wall upper portion 480 is in a firstplane 420. The first plane 420 can be parallel to the loft plane 401,thus the rear wall upper portion 480 is parallel to the loft plane 401.In some embodiments, the first plane 420 can be offset from the loftplane 401 at a distance between 0.210 inches to 0.280 inches. In someembodiments, the first plane 420 can be offset from the loft plane 401between 0.210 inches to 0.215 inches, 0.215 inches to 0.220 inches,0.220 inches to 0.225 inches, 0.225 inches to 0.230 inches, 0.230 inchesto 0.235 inches, 0.235 inches to 0.240 inches, 0.240 inches to 0.245inches, 0.245 inches to 0.250 inches, 0.250 inches to 0.255 inches,0.255 inches to 0.260 inches, 0.260 inches to 0.265 inches, 0.265 inchesto 0.270 inches, 0.270 inches to 0.275 inches, or 0.275 inches to 0.280inches. In one exemplary embodiment, the first plane 420 is offset fromthe loft plane 401 at a distance of 0.255 inches. Similarly, in someembodiments, the rear wall upper portion 480 can be offset from the loftplane 401 at a distance between 0.210 inches to 0.280 inches. In someembodiments, the rear wall upper portion 480 can be offset from the loftplane 401 between 0.210 inches to 0.215 inches, 0.215 inches to 0.220inches, 0.220 inches to 0.225 inches, 0.225 inches to 0.230 inches,0.230 inches to 0.235 inches, 0.235 inches to 0.240 inches, 0.240 inchesto 0.245 inches, 0.245 inches to 0.250 inches, 0.250 inches to 0.255inches, 0.255 inches to 0.260 inches, 0.260 inches to 0.265 inches,0.265 inches to 0.270 inches, 0.270 inches to 0.275 inches, or 0.275inches to 0.280 inches. In one exemplary embodiment, the rear wall upperportion 480 is offset from the loft plane 401 at a distance of 0.255inches.

Referring to FIG. 31 , the rear wall upper portion 480 can be comprisedof a rear wall upper portion interior surface 459 and a rear wall upperportion exterior surface 455. The thickness of the rear wall upperportion 480 can be measured between the rear wall upper portion interiorsurface 459 and a rear wall upper portion exterior surface 455. The rearwall upper portion thickness 435 can be minimized to push more massdownward and forward, lowering the CG, while still allowing the L-shapedfaceplate 450 and the sole 412 to flex. The rear wall upper portionthickness 435 can be held constant across the entirety of the rear wallupper portion 480. In some embodiments, the rear wall upper portionthickness 435 can be between 0.01 inches to 0.04 inches. In someembodiments, the rear wall upper portion thickness 435 can be between0.01 inches to 0.015 inches, 0.015 inches to 0.02 inches, 0.02 inches to0.025 inches, 0.025 inches to 0.03 inches, 0.03 inches to 0.035 inches,or 0.035 inches to 0.40 inches. In one exemplary embodiment, the rearwall upper portion thickness 435 can be 0.030 inches.

As described above, the weight pad forward edge 477 can extend down tothe sole 412 and the undercut. In some embodiments, the weight padforward edge 477 may not touch the sole return 454 in order to notrestrict the movement and flexure of the L-shaped faceplate 450. Theweight pad forward edge 477 can be offset from the upper region 467 tofurther push mass lower and forward to increase performancecharacteristics.

Referring to FIGS. 29-30 , the rear wall upper portion interior surface459 lies in a first plane 420, the upper region 467 of the weight padforward edge 477 lies in a second plane 421, and the lower region 469 ofthe weight pad forward edge 477 lies in a third plane 423. The firstplane 420 and third plane 423 are parallel to the loft plane 401. Thesecond plane 421 intersects the loft plane 401, first plane 420 andthird plane 423 so as to forms an acute angle relative to the plane inwhich the rear wall interior surface 439 lies. The position and natureof the upper region 467 within this second plane 421 allows the lowerregion 469 of the weight pad forward edge 477 to be offset from the rearwall upper portion interior surface 459 to force the CG lower andforward to reduce heel to toe gearing resulting in a higher ball speed.This offset can additionally decrease the internal cavity volumeallowing for reduced vibration amplitude at impact. The reducedamplitude increases the overall experience of the golf club due to thedecreased noise heard when using the golf club.

In some embodiments the third plane 423 can be offset in a perpendiculardirection from the first plane 420 at a distance between 0.025 inchesand 0.075 inches. In some embodiments, the third plane 423 can be offsetfrom the first plane 420 at a distance between 0.025 inches to 0.032inches, 0.032 inches to 0.039 inches, 0.039 inches to 0.046 inches,0.046 inches to 0.053 inches, 0.053 inches to 0.060 inches, 0.060 inchesto 0.067 inches, or 0.067 inches to 0.075 inches. In one exemplaryembodiment, the third plane 423 can be offset from the first plane 420at a distance of 0.050 inches. Additionally, the first plane can beoffset from the loft plane similarly as described above for FIGS. 25-28.

In some embodiments the lower region 469 of the weight pad forward edge477 can be offset from the rear wall upper portion interior surface 459at a distance between 0.025 inches and 0.075 inches. In someembodiments, the lower region 469 of the weight pad forward edge 477 canbe offset from the rear wall upper portion interior surface 459 at adistance between 0.025 inches to 0.032 inches, 0.032 inches to 0.039inches, 0.039 inches to 0.046 inches, 0.046 inches to 0.053 inches,0.053 inches to 0.060 inches, 0.060 inches to 0.067 inches, or 0.067inches to 0.075 inches. In one exemplary embodiment, the lower region469 of the weight pad forward edge 477 can be offset from the rear wallupper portion interior surface 459 at a distance of 0.050 inches.

The second plane 421 can be defined tangent with the first plane 420. Anangle Θ can further be defined between the first plane 420 and thesecond plane 421. In some embodiments, Θ can be between 5 degrees and 25degrees. In some embodiments, Θ can be between 5 degrees to 8 degrees, 8degrees to 11 degrees, 11 degrees to 14 degrees, 14 degrees to 17degrees, 17 degrees to 20 degrees, 20 degrees to 23 degrees, or 23degrees to 25 degrees. In some embodiments, Θ can be between 5 degreesto 15 degrees, 10 degrees to 20 degrees, or 15 degrees to 25 degrees. Inone exemplary embodiment, α can be 16 degrees.

In some embodiments, the volume of the internal cavity can be between0.555 in³ and 0.955 in³. In some embodiments, the volume of the internalcavity between 0.555 in³ to 0.600 in³, 0.600 in³ to 0.655 in³, 0.655 in³to 0.700 in³, 0.700 in³ to 0.755 in³, 0.755 in³ to 0.800 in³, 0.800 in³to 0.855 in³, 0.855 in³ to 0.900 in³, or 0.900 in³ to 0.955 in³. In oneexemplary embodiment, the volume of the internal cavity can be 0.772in³.

In some embodiments, the rear wall upper portion interior surface 459can cover between 55% and 65% of the rear wall interior surface 439. Insome embodiments, the rear wall upper portion interior surface 459 cancover between 55% to 57%, 57% to 59%, 59% to 61%, 61% to 63%, or 63% to65% of the rear wall interior surface 439. In one exemplary embodiment,the rear wall upper portion interior surface 459 can cover 60% of therear wall interior surface 439. In some embodiments, the upper region467 of the weight pad forward edge 477 can cover between 15% and 25% ofthe rear wall interior surface 439. In some embodiments, the upperregion 467 of the weight pad forward edge 477 can cover between 15% to17%, 17% to 19%, 19% to 21%, 21% to 23%, or 23% to 25% of the rear wallinterior surface 439. In one exemplary embodiment, the upper region 467of the weight pad forward edge 477 can cover 20% of the rear wallinterior surface 439. In some embodiments, the lower region 469 of theweight pad forward edge 477 can cover between 15% and 25% of the rearwall interior surface 439. In some embodiments, the lower region 469 ofthe weight pad forward edge 477 can cover between 15% to 17%, 17% to19%, 19% to 21%, 21% to 23%, or 23% to 25% of the rear wall interiorsurface 439. In one exemplary embodiment, the lower region 469 of theweight pad forward edge 477 can cover 20% of the rear wall interiorsurface 439.

Referring to FIG. 32-33 , aligned with the orientation of the rear wallupper portion interior surface 459, in some embodiments, the upperregion 467 of the weight pad forward edge 477 can span from the lowerheel region 434 to the central toe region 436 across the rear wallinterior surface 439. The upper region 467 of the weight pad forwardedge 477 can follow the angles of the shelf surface. The angling of theupper region 467 of the weight pad forward edge 477 can allow for moremass to be located in the toe portion. Extra mass can push the CG into amore central location to reduce any heel to toe gearing. The extra masscan also lead to optimizing MOI and improving performancecharacteristics.

In this exemplary embodiment, the undercut depth, undercut height, andrear wall geometry can also be described similar to the embodiments ofFIGS. 25-28 .

C. Overhanging Weight Pad with Angled Surface

FIG. 34 discloses an embodiment of a club head 400, similar to that ofFIGS. 25-28 , comprising an angled surface with a weight pad 4000 thatis continuous with the rear wall upper portion 480. The weight pad 4000can comprise several features of the embodiments described above, suchas a weight pad forward edge 477 and a rear wall upper portion interiorsurface 459. These features continue to cooperate with the L-shapedfaceplate 450 to enhance the flexibility of the faceplate 450 to improveball speed and launch characteristics. In this exemplary embodiment,similar to the embodiments described above, the rear wall upper portioninterior surface 459 can lie on the first plane 420. In this embodiment,the upper region 467 and lower region 469 of the weight pad forward edge477 also lie in the first plane 420. As previously described, the weightpad forward edge 477 is coupled to and extends continuously from therear wall upper portion interior surface 459. Further, a portion of theweight pad 4000 can overhang the sole return 454, without contacting thefaceplate 450. The weight pad 4000 allocates a greater portion of masstowards the sole 412 of the golf club head 400, driving the CG positionof the club head 400 lower, while allowing space for the faceplate 450to deflect.

In this exemplary embodiment, the first plane 420 can be offset from,and non-parallel with the loft plane 401. Thus, the rear wall upperportion interior surface 459, upper region 467 of the weight pad forwardedge 477, and lower portion of the weight pad forward edge 477 arenon-parallel with the loft plane 401. As previously described, anglingthe rear wall upper portion interior surface 459 and the weight padforward edge 477 relative to the loft plane 401 moves the club head masslower and more forward. This lowers the club head CG, while allowing thefaceplate 450 to deflect. In some embodiments, the angle between theloft plane 401 and first plane 420 can be between 1 degree and 5degrees. In some embodiments, the angle between the loft plane 401 andfirst plane 420 can be between 5 degrees to 8 degrees, 8 degrees to 11degrees, 11 degrees to 14 degrees, 14 degrees to 17 degrees, 17 degreesto 20 degrees, 20 degrees to 23 degrees, or 23 degrees to 25 degrees. Inone preferred embodiment, the angle between the loft plane 401 and firstplane angle can be 5 degrees.

In another embodiment, the golf club head 400 can comprise aperpendicular distance, relative to the loft plane 401, between thefirst plane 420 and the loft plane 401. The perpendicular distance canvary at points along the loft plane 401. In a preferred embodiment, theperpendicular distance decreases from a point nearest the top rail 410to a point nearest the sole 412. Therefore, the perpendicular offsetdistance between the loft plane 401 and the first plane 420 is greatertowards the top rail 410 of the golf club head 400 than towards the sole412. This moves more club head mass forward, improving ball speed andlaunch characteristics. In some embodiments the perpendicular offsetbetween the first plane 420 and the loft plane 401 can vary a distancebetween 0.01 inches and 0.25 inches. In some embodiments, theperpendicular offset can vary a distance between 0.01 inches to 0.05inches, 0.05 inches to 0.09 inches, 0.09 inches to 0.13 inches, 0.13inches to 0.17 inches, 0.17 inches to 0.21 inches, or 0.21 inches to0.25 inches. In one exemplary embodiment, the perpendicular offset canvary a distance between 0.15 inches to 0.20 inches. In an alternativeembodiment, the perpendicular distance can be greater at a heelwardpoint than at a toeward point. Alternatively, the perpendicular distancecan be greater at a toeward point than at a heelward point. Varying theperpendicular offset distance in a heel-toe direction allows club headmass to be redistributed to ensure proper MOI characteristics.

The thickness 435 of the rear wall upper portion 480, as previouslydescribed, can be minimized to push more mass downward and forward,lowering the CG, while still allowing the L-shaped faceplate 450 and thesole 412 to flex. A thin rear wall upper portion 480 can also allow thebody of the club head 400 to flex more, like a diving board effect. In apreferred embodiment, the rear wall upper portion thickness 435 can beheld constant across the entirety of the rear wall upper portion 480. Inother embodiments, the rear wall upper portion thickness 435 can vary.In some embodiments, the rear wall upper portion thickness 435 can bebetween 0.010 inches to 0.040 inches. In some embodiments, the rear wallupper portion thickness 435 can be between 0.010 inches and 0.015inches, 0.015 inches and 0.020 inches, 0.020 inches and 0.025 inches,0.025 inches and 0.030 inches, 0.030 inches and 0.035 inches, or 0.035inches and 0.040 inches. In one exemplary embodiment, the rear wallupper portion thickness 435 can be 0.030 inches. In another exemplaryembodiment, the rear wall upper portion thickness 435 can be 0.032inches.

In this exemplary embodiment, the undercut depth, undercut height,internal cavity volume, rear wall upper/lower portion interior surfacecoverages can also be described similar to the embodiments of FIGS.25-33 .

D. Overhanging Weight Pad with Angled Lower Region

FIG. 35 discloses an embodiment comprising an overhanging weight pad4000 and an angled lower region. Similar to the embodiment of FIGS.25-33 , the rear wall interior surface 439 can comprise several featuresof the embodiments described above, as well as portions that rest onseparate planes. These features continue to cooperate with the L-shapedfaceplate 450 to enhance the flexibility of the faceplate 450 to improveball speed and launch characteristics. In this embodiment, the rear wallupper portion interior surface 459 can lie on the first plane 420, whilethe, the upper region 467 and lower region 469 of the weight pad forwardedge 477 lie in the second plane 421. Thus, the rear wall upper portioninterior surface 459 is non-coplanar with the upper region 467 and lowerregion 469 of the weight pad forward edge 477. The rear wall interiorsurface 439 consisting of two non-coplanar surfaces places more massforward, creating more overhang for the weight pad 4000. The greateroverhang of the weight pad 4000 increases the forward mass of the golfclub head 400, which improves golf ball launch characteristics.

In a preferred embodiment, the first plane 420 can be parallel with theloft plane 401. In an alternate embodiment, the first plane 420 and/orthe second plane 421 are non-parallel with the loft plane 401. In someembodiments, the angle between the loft plane 401 and first plane 420can be between 0.5 degree and 3 degrees. In some embodiments, the anglebetween the first plane 420 and second plane 421 can be between 3degrees to 5 degrees, 5 degrees to 8 degrees, 8 degrees to 11 degrees,11 degrees to 14 degrees, 14 degrees to 17 degrees, 17 degrees to 20degrees, or 20 degrees to 23 degrees. In one exemplary embodiment, theangle between the loft plane 401 and the first plane 420 can be 3degrees. In other embodiments, as depicted in FIG. 35 , the anglebetween the first plane 420 and the second plane 421, Θ, can be between1 and 3 degrees. In some embodiments, the angle between first plane 420and the second plane 421 can be between 3 degrees to 5 degrees, 5degrees to 8 degrees, 8 degrees to 11 degrees, 11 degrees to 14 degrees,14 degrees to 17 degrees, 17 degrees to 20 degrees, 20 degrees to 23degrees, or 23 degrees to 25 degrees. In one exemplary embodiment, theangle between the first plane 420 and the second plane 421, Θ, can be 5degrees.

The perpendicular distance, as described in previous embodiments, can begreater at a point along the weight pad forward edge 477 nearest the toprail 410 than at a point nearest the sole 412. This perpendicular offsetdirectly corresponds with the weight pad forward edge 477 being askewrelative to the rear wall upper portion interior surface 459.Specifically, the weight pad forward edge 477 is angled relative to therear wall upper portion interior surface 459, thereby allowing the CG tobe moved further down and forward through the distribution of masswithin the club head 400. The angling of the weight pad forward edge 477can also decrease the internal cavity volume allowing for reducedamplitude of the golf club head 400 at impact. The reduced amplitudeincreases the overall experience of the golf club due to the decreasednoise heard when using the golf club.

The thickness 435 of the rear wall upper portion 480, as previouslydescribed, can be minimized to push more mass downward and forward,lowering the CG, while still allowing the faceplate 450 to flex. A thinrear wall upper portion 480 can also allow the body of the club head 400to flex more. In some embodiments, the rear wall upper portion thickness435 can be held constant across the entirety of the rear wall upperportion 480. In some embodiments, the rear wall upper portion thickness435 can be up to 0.010 inches. In some embodiments, the rear wall upperportion thickness 435 can be up to 0.20 inches. In other embodiments,the rear wall upper portion thickness 435 can be up to 0.030 inches. Inother embodiments, the rear wall upper portion thickness 435 can be upto 0.040 inches. In one exemplary embodiment, the rear wall upperportion thickness 435 can be 0.030 inches. In another exemplaryembodiment, the rear wall upper portion thickness 435 can be 0.032inches.

Similar to the embodiments of FIGS. 29-33 , the upper region 467 of theweight pad forward edge 477 can span from the lower heel region 434 tothe central toe region 436 across the rear wall interior surface.Specifically, the upper region 467 of the weight pad forward edge 477can follow the angles of the shelf surface, similar to the embodimentsdescribed above. This slant of the upper region 467 of the weight padforward edge 477 can allow for more mass to be located in the toeportion. As previously described, extra mass is needed to push the CGinto a more central location to reduce any heel to toe gearing, therebyenhancing MOI and improving performance characteristics.

In these exemplary embodiments, the rear wall internal surface, weightpad forward edge 477, first plane 420, and second plane 421 can beoffset in a perpendicular direction from the loft plane at distancessimilar to the embodiments of FIGS. 25-33 . Further, the undercut depth,undercut height, internal cavity volume, rear wall upper/lower portioninterior surface coverages can also be described similar to theembodiments of FIGS. 25-33 .

III. Rear Wall with Rear Exterior Cavity

In many embodiments, the rear wall 140 of the club head 100 comprises ageometry that forms a rear exterior cavity 198. In some embodiments, therear exterior cavity 198 can be configured to receive a badge 199 thatdamps vibrations and/or provides an aesthetically pleasing appearance.The geometry of the rear wall 140 can also increase the flexibility ofthe club head 100, leading to increased ball speeds.

Referring to FIGS. 12-16 , the rear wall 140 extends upward from therear body sole portion 138 to the rear body top rail portion 132 andencloses the rear end 104 of the club head 100. The rear wall 140comprises a rear wall upper portion 180, a rear wall upper transition182, a rear wall middle portion 184, a rear wall lower portion 188, arear wall lower transition 186, and a rear wall toe portion 189. Everyportion 180, 182, 184, 186, 188, 189 of the rear wall 140 furthercomprises an exterior surface and an interior surface. The rear wallupper portion 180 extends toward the sole 112 from the rear body toprail portion 132 parallel to the loft plane 101 defined by the strikeface 116. The rear wall upper transition 182 extends toward the frontend 102 and the strike face 116 into the hollow interior cavity 114. Therear wall middle portion 184 extends approximately toward the sole 112from the rear wall upper transition 182 to the rear wall lowertransition 186. The rear wall lower transition 186 extends rearward fromthe rear wall middle portion 184, away from the strike face 116. Therear wall 140 further comprises a rear wall toe transition 194 betweenthe rear wall middle portion 184 and the rear wall toe portion 189. Therear wall toe transition 194 can connect the rear wall upper transition182 and the rear wall lower transition 186 at the toe end 108. In manyembodiments, as shown in FIG. 14 , the rear wall upper transition 182and the rear wall lower transition 186 can come together at a point nearthe heel end 106. In other embodiments, the rear wall 140 can furtherdefine a rear wall heel transition connecting the rear wall uppertransition 182 and the rear wall lower transition 186 at the heel end106. The rear wall middle portion 184 can therefore be bounded by therear wall lower transition 186, the rear wall toe transition 194, andthe rear wall upper transition 182.

Due to the hollow-body nature of the club head 100, the top rail and therear wall 140 can be substantially thin without sacrificing durability.The thin top rail and rear wall 140 increase flexure within the top railand rear wall 140 portions thereby to increase ball speed.

As illustrated in FIG. 15 , the top rail thickness 174 can besubstantially thin to increase the flexure of rear body top rail portion132. The thinner the rear body top rail portion 132, the greater theflexibility of the club head 100, leading to higher ball speeds. In manyembodiments, the top rail thickness 174 can vary slightly. For example,in some embodiments, the top rail thickness 174 can be greatest near thefaceplate 150 and decrease towards the rear wall upper portion 180. Inother embodiments, the top rail thickness 174 can be substantiallyconstant from the faceplate 150 to the rear wall upper portion 180.

In many embodiments, the top rail thickness 174 can be less thanapproximately 0.070 inch, less than approximately 0.065 inch, less thanapproximately 0.060 inch, less than approximately 0.055 inch, less thanapproximately 0.050 inch, less than approximately 0.045 inch, less thanapproximately 0.040 inch, less than approximately 0.035 inch, less thanapproximately 0.030 inch, or less than approximately 0.025 inch. The toprail thickness 174 can be between 0.025 inch to 0.050 inch, 0.035 inchto 0.050 inch, 0.040 inch to 0.065 inch, or 0.045 inch to 0.070 inch. Inone exemplary embodiment, the top rail thickness is approximately 0.045inch.

A thin rear body top rail portion 132 with the thicknesses describedabove is only achievable in a hollow-body type iron. In order for therear body top rail portion 132 to be substantially thin, the club head100 requires a continuous rear wall 140 to provide structural support tothe rear body top rail portion 132. If the thin rear body top railportion 132 described above was applied to a cavity-back iron or a clubhead without a continuous rear wall 140, the rear body top rail portion132 would fail under the force of impact.

Referring to FIG. 15 , the rear wall 140 comprises a rear wall thickness178. The rear wall thickness 178 may be in a range of 0.030 inch to0.070 inch. The rear wall thickness 178 may vary in this range from therear body top rail portion 132 to the rear wall lower transition 186.The rear wall upper portion 180, the rear wall upper transition 182, therear wall middle portion 184, and the rear wall lower transition 186 caneach comprise a separate thickness 178. The rear wall lower portion 188is substantially thicker than the rest of the rear wall 140, as the rearwall lower portion 188 is integral with the weight pad 1000.

In many embodiments the rear wall thickness 178 can be less thanapproximately 0.070 inch, less than approximately 0.065 inch, less thanapproximately 0.060 inch, less than approximately 0.055 inch, less thanapproximately 0.050 inch, less than approximately 0.045 inch, less thanapproximately 0.040 inch, less than approximately 0.035 inch, less thanapproximately 0.030 inch, or less than approximately 0.025 inch. Therear wall thickness 178 can be between 0.025 inch to 0.050 inch, 0.035inch to 0.050 inch, 0.040 inch to 0.065 inch, or 0.045 inch to 0.070inch. In one exemplary embodiment, the top rail thickness isapproximately 0.045 inch. In one exemplary embodiment, the rear wallthickness 178 is approximately 0.045 inch. In another exemplaryembodiment, the rear wall thickness 178 is approximately 0.032 inch.

In some embodiments, the rear wall thickness 178 at each of the rearwall upper portion 180, the rear wall upper transition 182, the rearwall middle portion 184, and the rear wall lower transition 186 can besubstantially the same. In other embodiments, one or more of the rearwall thicknesses 178 at the rear wall upper portion 180, the rear wallupper transition 182, the rear wall middle portion 184, and/or the rearwall lower transition 186 can be different from one another.

The rear wall upper portion 180 defines an upper rear wall angle withthe rear wall upper transition 182. The upper rear wall angle is greaterthan 90 degrees. The rear wall middle portion 184 defines a lower realwall angle with the rear wall lower transition 186. The rear wall lowerangle is greater than 90 degrees. The rear wall middle portion 184exterior surface is essentially planar.

As illustrated in FIG. 14 , a rear wall middle portion plane 143intersects the loft plane 101 outside the golf club head 100 and abovethe rear body top rail portion 132. The rear wall middle portion plane143 defines a loft plane intersection angle 141 where it intersects theloft plane 101 that is in a range of 5 degrees to 25 degrees. In manyembodiments, the loft plane intersection angle 141 may be 5 degrees, 6degrees, 7 degrees, 8 degrees, 9 degrees, 10 degrees, 11 degrees, 12degrees, 13 degrees, 14 degrees, 15 degrees, 16 degrees, 17 degrees, 18degrees, 19 degrees, 20 degrees, 21 degrees, 22 degrees, 23 degrees, 24degrees, or 25 degrees.

In many embodiments, the rear wall upper portion 180 extends parallel tothe strike face portion of the L-shaped faceplate 150. As illustrated byFIG. 15 , the rear wall upper portion 180 is offset from the strike faceportion 152 by a rear wall upper portion offset distance 181. The rearwall upper portion offset distance 181 may be in a range of 0.100 inchto 0.300 inch, depending on the loft angle of the particular club head100. Because the rear wall upper portion 180 is parallel to the strikeface portion 152, the rear wall upper portion offset distance 181 isconstant and does not vary in a given golf club head 100.

The rear wall upper portion offset 181 protects the rear wall upperportion 180 from damage during welding. As discussed above, the rearbody 130 further comprises an opening proximate the front end 102 of theclub head 100, the opening being formed between the top rail 110, theheel end 106, the toe end 108, and the sole 112 of the rear body 130.The welding surfaces 146 extends around the perimeter of the rear bodyopening 144, the welding surfaces 146 being formed by forwardmost edgesof the rear body top rail portion 132, rear body heel portion 134, rearbody toe portion 136, and sole portion 138. The smaller the rear wallupper portion offset distance 181, the greater the flexure of the rearbody top rail portion 132 and rear wall upper portion 180. However, therear wall upper portion offset 181 must provide enough distance betweenthe welding surfaces 146 and the rear wall upper portion 180 to preventthe welding process from melting or distorting the rear wall upperportion 180. The club head 100 comprises a rear wall upper portionoffset distance 181 that increases rear wall 140 flexure without therear wall upper portion 180 being damaged during welding. In oneexemplary embodiment, the rear wall upper portion offset distance 181 isapproximately 0.188 inch.

Further, the rear wall middle portion 184 defines a rear wall middleportion offset distance 183. The rear wall middle portion offsetdistance 183 can be measured between an interior surface of the rearwall upper transition 182 and the strike face back surface 156. The rearwall middle portion offset distance 183 is as small as possible toencourage bending of the rear wall 140 without interfering with thebending of the faceplate 150.

In many embodiments, the rear wall middle portion offset distance 183can be greater than approximately 0.025 inch greater than approximately0.05 inch, greater than approximately 0.075 inch, greater thanapproximately 0.100 inch, greater than approximately 0.125 inch, greaterthan approximately 0.150 inch, greater than approximately 0.175 inch, orgreater than approximately 0.200 inch. In some embodiments, the rearwall middle portion offset distance 183 can be between 0.025 inch to0.095 inch, 0.070 inch to 0.100 inch, 0.080 inch to 0.125 inch, 0.120inch to 0.175 inch, 0.150 inch to 0.200 inch, or 0.175 inch to 0.300inch. In one exemplary embodiment, the rear wall middle portion offsetdistance 183 is approximately 0.09 inch.

As discussed above, the rear body 130 can comprise a weight pad 1000formed in the interior cavity 114 that overhangs a portion of the sole112 and/or a portion of the sole return 154. Referring to FIG. 15 , therear wall lower transition 186 interior surface extends rearward,further away from the strike face back surface 156. The rear wall middleportion plane 143 intersects the top wall 1020 of the weight pad 1000.The portion of the rear wall lower transition 186 interior surfacerearward of the rear wall middle portion plane 143, a radiusedtransition between rear wall lower transition 186 interior surface andthe weight pad top wall 1020, and the weight pad top wall 1020 rearwardof the rear wall middle portion plane 143 together define an upperinterior undercut 195. The upper interior undercut 195 comprises anupper interior undercut height 196 measured between the rear wall lowertransition 186 interior surface and the weight pad top wall 1020. Theupper interior undercut height 196 can vary in a range of approximately0.010 inch to approximately 0.200 inch. The upper interior undercut 195comprises an upper interior undercut depth 197 measured from the mostrearward point of the upper interior undercut 195 to the rear wallmiddle portion plane 143.

The upper interior undercut depth 197 can vary in a range ofapproximately 0.010 inch to approximately 0.300 inch. For example, theupper interior undercut depth 197 can range from 0.010 inch to 0.030inch, 0.030 inch to 0.050 inch, 0.050 inch to 0.070 inch, 0.070 inch to0.090 inch, 0.090 inch to 0.110 inch, 0.110 inch to 0.130 inch, 0.130inch to 0.150 inch, 0.150 inch to 0.170 inch, 0.170 inch to 0.190 inch,0.190 inch to 0.210 inch, 0.210 inch to 0.230 inch, 0.230 inch to 0.250inch, 0.250 inch to 0.270 inch, 0.270 inch to 0.290 inch, or 0.290 inchto 0.300 inch. The upper interior undercut depth 197 can be greater thanapproximately 0.010 inch, greater than approximately 0.015 inch, greaterthan approximately 0.020 inch, greater than approximately 0.025 inchgreater than approximately 0.05 inch, greater than approximately 0.075inch, greater than approximately 0.100 inch, greater than approximately0.125 inch, greater than approximately 0.150 inch, greater thanapproximately 0.175 inch, or greater than approximately 0.200 inch.

The rear wall lower transition 186 exterior surface is essentiallyplanar and extends essentially parallel to the ground plane 123 when thegolf club head 100 is in the address position. The rear wall toetransition 194 exterior surface is essentially planar. The rear wallupper transition 182 exterior surface, the rear wall lower transition186 exterior surface, the rear wall toe transition 194 exterior surface,and the rear wall middle portion 184 exterior surface cooperate todefine a rear exterior cavity 198. The rear wall middle portion 184 isrecessed from the rear wall exterior surface and by the rear wall lowertransition 186, the rear wall toe transition 194, and the rear wallupper transition 182. The rear exterior cavity 198 further comprises afillet or curved transition between the planar rear cavity exteriorsurface and the surrounding surfaces. The rear wall 130 geometry formingthe rear exterior cavity 198 can be combined with any of the variousL-shaped faceplate 150 geometries described above including a solereturn 154, a toe extension 168, a top rail extension 170, or anycombination thereof. The rear wall 130 geometry forming the rearexterior cavity 198 can also be combined with any other suitable rearbody 130 geometry or feature described either above or below, includinga sole ledge 148, an angled weight pad 1000, a weight pad 2000comprising an extension 2050, a heel mass 147 and/or toe mass 149, alower interior undercut 190, an upper interior undercut 195, an externalflexure hinge 3000, an internal bending notch 3100, an internal weldingrib 179, or any combination thereof.

In some embodiments, as illustrated in FIG. 16 , a badge 199 may beapplied to the exterior surface of the golf club head rear wall 140. Thebadge 199 may be applied on the rear wall middle portion 184 exteriorsurface. In some embodiments, the badge 199 comprises an inner adhesivebadge layer and an outer, metallic badge layer permanently affixed tothe inner adhesive badge layer. As discussed above, the rear wall middleportion 184 is planar. Further, the rear wall middle portion 184 iswithin the rear exterior cavity 198. As a result, the badge 199 isapplied and contained entirely within the rear exterior cavity 198.Further, the badge 199 may also be planar. Further the badge 199 cancomprise a thickness. The thickness of the badge 199 may be constant.The thickness of the badge 199 may vary within the badge 199. In manyembodiments, it is desirable to produce a badge 199 having a constantbadge thickness, because a planar, constant thickness badge isconsiderably less expensive than a non-planar, varied thickness badge.The badge thickness may vary in range between 0.010 inch and 0.500 inch.The badge 199 is formed such that it does not protrude rearwardly pastthe rear wall upper portion 180 or rear wall lower portion 188 exteriorsurfaces.

Referring to FIG. 16 , the badge 199 covers a substantial portion of therear wall 140. The badge 199 comprises a surface area exposed on therear end 104 of the club head 100. The surface area of the badge 199 canbe between 1.00 in² to 2.00 in². In some embodiments, the surface areaof the badge 199 can be between 1.00 in² to 1.25 in², between 1.10 in²to 1.45 in², between 1.30 in² to 1.55 in², between 1.50 in² to 1.75 in²,or between 1.70 in² to 2.00 in². In some embodiments, the badge 199covers a substantial portion of the rear wall 140. In some embodiments,the badge 199 covers between 10% to 30%, between 25% to 40%, between 30%to 50%, between 45% to 60%, between 50% to 75%, between 60% to 75%, orbetween 70% to 80% of the surface area of the rear wall 140. The badge199 can cover a substantial portion of the rear wall 140 to providevibrational damping and/or acoustic benefits to the club head 100.

In some embodiments, as illustrated in FIG. 5 , the rear wall 140 canform an internal welding rib 179. The internal welding rib 179 comprisesan area of increased thickness along the rear wall 140 that protects therear wall 140 during the welding process. The internal welding rib 179is located on the rear wall 140 proximate the heel end 106 and extendssubstantially vertically. The internal welding rib 179 can extend atleast partially between the rear body top rail portion 132 and the rearbody sole portion 138. In many embodiments, the internal welding rib 179can extend toward the sole 112 from near the rear body top rail portion132 and terminate just above the weight pad top wall 1020 and/or a topsurface of the heel mass 147. As a function of its increased thickness,the internal welding rib 179 protrudes into the hollow interior cavity114 from the interior surface of the rear wall 140. In some embodiments,the internal welding rib 179 can protrude from the interior surface(s)of the rear wall upper portion 180, the rear wall upper transition 182,the rear wall middle portion 184, the rear wall lower transition 186,and/or the rear wall lower portion 188.

From a front view, as illustrated by FIG. 5 , the internal welding rib179 can be located near the heel end 106 of the club head 100. Theinternal welding rib 179 can be located on the rear body 130 directlybehind the location of the heel side perimeter edge 162 of the faceplate150. Because the heel side perimeter edge 162 is welded in a directionperpendicular to the rear wall 140, the area of the rear wall 140 behindthe weld line can be reinforced by the internal welding rib 179 toprotect the rear wall 140 from damage or discoloration that may occurduring the welding process. In many embodiments, the thickness of theinternal welding rib 179 can be between 0.060 inch to 0.140 inch. Thethickness of the internal welding rib 179 can be between 0.060 inch to0.080 inch, 0.075 inch to 0.100 inch, 0.090 inch to 0.120 inch, or 0.110inch to 0.140 inch. The thickness of the internal welding rib 179 can begreater than approximately 0.060 inch, greater than approximately 0.065inch, greater than approximately 0.070 inch, greater than approximately0.075 inch, greater than approximately 0.080 inch, greater thanapproximately 0.085 inch, greater than approximately 0.090 inch, greaterthan approximately 0.095 inch, greater than approximately 0.100 inch,greater than approximately 0.105 inch, greater than approximately 0.110inch, greater than approximately 0.115 inch, greater than approximately0.120 inch, greater than approximately 0.125 inch, greater thanapproximately 0.130 inch, greater than approximately 0.135 inch, orgreater than approximately 0.140 inch. In many embodiments, thethickness of the internal welding rib 179 can be approximately doublethe rear wall thickness 178.

The internal welding rib 179 can be combined with any of the variousL-shaped faceplate 150 geometries described above including a solereturn 154, a toe extension 168, a top rail extension 170, or anycombination thereof. The internal welding rib 179 can also be combinedwith rear body 130 geometry or feature described either above or below,including a sole ledge 148, an angled weight pad 1000, a weight pad 2000comprising an extension 2050, a heel mass 147 and/or toes mass 149, alower interior undercut 190, an upper interior undercut 195, a rearexterior cavity 198, an external flexure hinge 3000, an internal bendingnotch 3100, an internal welding rib 179, or any combination thereof.

IV. Dynamic Lofting Features

Referring now to embodiments illustrated at FIGS. 17-19 , the rear body330 of a golf club head 300 can comprise one or more dynamic loftingfeatures. The one or more dynamic lofting features provide increasedflexure of the rear body 330, particularly increasing the bending of therear wall 340. The dynamic lofting features further increase the dynamicloft of the club head 300 at impact. Dynamic loft refers to the increaseor decrease in loft angle at impact due to the collision between theclub head 300 and the golf ball. An increase in dynamic loft provides ahigher launch without sacrificing ball speed. Flexure of the rear wall340 at impact influences the dynamic loft of the club head 300. Inparticular, the greater rearward rotation of the rear wall 340 relativeto the sole will increase dynamic loft. The dynamic lofting featuresincrease the club head dynamic loft by enabling an upper portion of therear wall 340 to bend rearward at impact. In many embodiments, the oneor more dynamic lofting features can comprise a flexure hinge and/or aninternal bending notch. The third embodiment of the club head 300 issubstantially similar to club head 100, but for the inclusion of thedynamic lofting features. Club head 300 can comprise similar features toclub head 100, labeled with a 300 numbering scheme (i.e., club head 300comprises a rear body 330, a faceplate 350, etc.).

A. Flexure Hinge

As illustrated in FIGS. 17, 18A, 18B, 18C, and 18D the club head 300comprises a flexure hinge 3000 extending in a heel-to-toe directionalong the rear wall 340. The club head 300 comprising the flexure hinge3000 facilitates rotational bending of the rear wall 340 about the soleto increase the dynamic loft of the golf club head 300.

Referencing FIGS. 17, 18A, 18B, 18C, and 18D of the drawings, the rearwall 340 can be bifurcated in a lengthwise direction by the flexurehinge 3000. The flexure hinge 3000, therefore, defines a rear wall upperportion 380 and a rear wall lower portion 388. The rear wall upperportion 380 can be defined between the top rail 310 and the flexurehinge 3000, and the rear wall lower portion 388 can be defined betweenthe sole and the flexure hinge 3000.

As discussed above, the flexure hinge 3000 extends in a heel-to-toedirection along the rear wall 340. The flexure hinge 3000 comprises ahinge heel end 3010 and a hinge toe end 3012 opposite the hinge heel end3010. In some embodiments, as illustrated in FIG. 19 , the flexure hinge3000 can extend the entire heel-to-toe length of the rear wall 340 suchthat the hinge heel end 3010 is located proximate the heel sideperiphery 322, and the hinge toe end 3012 is located proximate the toeside periphery 324. In other embodiments, the flexure hinge 3000 may notextend the entire heel-to-toe length of the rear wall 340, such that atleast one of the hinge heel end 3010 and the hinge toe end 3012terminate in the middle of the rear wall 340, and are spaced away fromthe club head peripheries.

FIG. 18B illustrates a zoomed in cross sectional view of a golf clubhead 300 comprising the above flexure hinge 3000. As illustrated, theflexure hinge 3000 can comprise a top surface 3014, a bottom surface3016, and a nadir 3020 forming a transition between the hinge topsurface 3014 and the hinge bottom surface 3016. The hinge top surface3014 and the hinge bottom surface 3016 can each be angled toward thefront end 302 of the club head 300. In this orientation, the flexurehinge 3000 protrudes into the interior cavity 314 and the nadir 3020defines the portion of the flexure hinge 3000 closest to the front end302 of the club head 300. The flexure hinge 3000 strategically weakens aportion of the rear wall 340 by creating a groove in the rear wall 340to promote bending in the area of the rear wall 340 that comprises theflexure hinge 3000. The flexure hinge 3000 allows the rear wall 340 tobend over the entire heel to toe length of the club head 300. In otherwords, the flexure hinge 3000 allows the rear wall upper portion 380 tobend rearward, about the sole, at impact. The flexure hinge 3000increases the dynamic loft of the club head 300 and creates a club head300 that stores a greater amount of spring energy to be transferred tothe golf ball, increasing ball speed.

As discussed above, the flexure hinge 3000 protrudes into the interiorcavity 314 relative to the adjacent surfaces of the rear wall 340. Froma rear view, as illustrated in FIG. 19 , the flexure hinge 3000 createsa groove recessed within the rear wall 340. In some embodiments, thegroove can comprise a variable width such that the groove is widercloser to the heel end 306 than the toe end or wider closer to the toeend than the heel end 306. In many embodiments, such as the embodimentillustrated in FIG. 17 , the groove can comprise a width that issubstantially constant. The width of the groove can be determined by aflexure hinge height 3030, as described in further detail below.

In some embodiments, such as the embodiment of FIGS. 18A and 18B, theflexure hinge 3000 can comprise a generally semi-elliptical shape whenviewed in cross-section. The semi-elliptical flexure hinge 3000 cancomprise a top surface 3014, a bottom surface 3016, and asemi-elliptical nadir 3020. The semi-elliptical nadir 3020 can have aradius defining the curve of the hinge. In some embodiments the nadir3020 can have a radius of curvature between 0.050 inch and 0.70 inch.For example, the nadir 3020 can have a radius of curvature of 0.050inch, 0.055 inch, 0.060 inch, 0.065 inch, or 0.070 inch. In otherembodiments, the flexure hinge 3000 can comprise a generallysemi-circular shape, a triangular shape, a rectangular shape, an ovularshape, or any other suitable shape for allowing the rear wall 340 toflex and increase dynamic loft.

Referring to FIG. 18B, the flexure hinge 3000 can comprise a hinge width3060 measured as the distance between the top surface 3014 and thebottom surface 3016, in a vertical direction. The hinge width 3060 canrange from 0.050 inch to 0.150 inch. For example, the hinge width 3060can be 0.050 inch, 0.060 inch, 0.070 inch, 0.080 inch, 0.090 inch, 0.100inch, 0.110 inch, 0.120 inch, 0.130 inch, 0.140 inch, or 0.150 inch. Insome embodiments, the hinge width 3060 can be between 0.050 inch and0.060 inch, 0.060 inch and 0.070 inch, 0.070 inch and 0.080 inch, 0.080inch and 0.090 inch, 0.090 inch and 0.100 inch, 0.100 inch and 0.110inch, 0.110 inch and 0.120 inch, 0.120 inch and 0.130 inch, 0.130 inchand 0.140 inch, or 0.140 inch and 0.150 inch. As the flexure hinge width3060 increases, the potential for bending increases.

The top surface 3014 and bottom surface 3016 of the flexure hinge 3000can comprise a top surface depth 3040 and a bottom surface depth 3050.The top surface depth 3040 can be measured as the linear distancebetween a bottom edge of the upper portion 380 and the nadir 3020. Thebottom surface depth 3050 can be measured as the linear distance betweena top edge of the lower portion 388 and the nadir 3020. In someembodiments the top surface depth 3040 ranges from approximately 0.080inch to approximately 0.150 inch. For example, the top surface depth3040 can be 0.080 inch, 0.085 inch, 0.090 inch, 0.095 inch, 0.100 inch,0.105 inch, 0.110 inch, 0.115 inch, 0.120 inch, 0.125 inch, 0.130 inch,0.135 inch, 0.140 inch, 0.145 inch, or 0.150 inch. Likewise, in someembodiments, the bottom surface depth 3050 can range from approximately0.120 inch to approximately 0.260 inch. For example, the bottom surfacedepth 3050 can be 0.120 inch, 0.130 inch, 0.140 inch, 0.150 inch, 0.160inch, 0.170 inch, 0.180 inch, 0.190 inch, 0.200 inch, 0.210 inch, 0.220inch, 0.230 inch, 0.240 inch, 0.250 inch, or 0.260 inch. In someembodiments, the top surface depth 3040 and the bottom surface depth3050 vary from the hinge heel end 3010 to the hinge toe end 3012. Forexample, the bottom surface depth 3050 can increase from the hinge heelend 3010 to the hinge toe end 3012. In other embodiments, the topsurface depth 3040 and bottom surface depth 3050 can be constant fromthe hinge heel end 3010 to the hinge toe end 3012.

In other embodiments, as illustrated in FIGS. 18C and 18D, rather than agroove, the flexure hinge 3001 can be formed as a crease between therear wall upper portion 380 and the rear wall lower portion 388. Therear wall upper portion 380 and the rear wall lower portion 388 cometogether and form the nadir 3020 such that the rear wall upper portion380 and the rear wall lower portion 388 are approximately perpendicular.In this particular embodiment, the top surface 3014 and the bottomsurface 3016 are synonymous with the rear wall upper portion 380 and therear wall lower portion 388. The flexure hinge 3001, as illustrated inFIGS. 18C and 18D, the top surface depth 3040, bottom surface depth3050, and the hinge width are 0 or negligible, as the flexure hinge 3001is not recessed within the rear wall.

As shown in FIG. 17 , the flexure hinge 3001 can further comprise ahinge height 3030 measured as the vertical distance of the nadir 3020from a ground plane 3002. The hinge height 3030 can be measured at anypoint along the heel-to-toe length of the flexure hinge 3001. In someembodiments, the flexure hinge 3001 comprises a hinge height 3030 thatis constant across the heel to toe length of the flexure hinge 3001. Inother embodiments the hinge height 3030 varies across the heel-to-toelength of the flexure hinge 3001. In some embodiments, the flexure hinge3001 is located in a substantially low position of the club head 300.

Providing the flexure hinge 3001 substantially low on the rear wall 340increases the amount the rear wall upper portion 380 bends rearward atimpact. The rearward bending of the rear wall upper portion 380 iscreated by a torque applied about the flexure hinge 3001 by the force ofimpact. The lowering of the flexure hinge 3001 on the rear wall 340provides a longer moment arm between the impact force and the flexurehinge 3001, increases the torque, and creates a greater rearward bend ofthe rear wall upper portion 380. in some embodiments, the flexure hinge3001 can be parallel to the ground plane 3002. In other embodiments, theflexure hinge 3001 can form an angle with the ground plane 3002 rangingfrom 0.1 degrees to 45 degrees.

The embodiment of FIG. 19 illustrates a club head 300 with a varyinghinge height 3030. Specifically, the hinge height 3030 increaseslinearly from the hinge heel end 3010 to the hinge toe end 3012. In manyembodiments, the hinge height 3030 at the hinge toe end 3012 can rangefrom 0.78 inch to 0.96 inch. For example, the hinge height 3030 at thehinge toe end 3012 can be 0.78 inch, 0.79 inch, 0.80 inch, 0.81 inch,0.82 inch, 0.83 inch, 0.84 inch, 0.85 inch, 0.86 inch, 0.87 inch, 0.88inch, 0.89 inch, 0.90 inch, 0.91 inch, 0.92 inch, 0.93 inch, 0.94 inch,0.95 inch, or 0.96 inch. In some embodiments the hinge height 3030 atthe hinge toe end 3012 can be between 0.78 inch and 0.80 inch, 0.80 inchand 0.82 inch, 0.82 inch and 0.84 inch, 0.84 inch and 0.86 inch, 0.86inch and 0.88 inch, 0.88 inch and 0.90 inch, 0.90 inch and 0.92 inch,0.92 inch and 0.94 inch, or 0.94 inch and 0.96 inch. In someembodiments, the hinge height 3030 at the hinge heel end 3010 can rangefrom 0.15 inch to 0.28 inch. The hinge height 3030 at the hinge heel end3010 can be 0.15 inch, 0.16 inch, 0.17 inch, 0.18 inch, 0.19 inch, 0.20inch, 0.21 inch, 0.22 inch, 0.23 inch, 0.24 inch, 0.25 inch, 0.26 inch,0.27 inch or 0.28 inch. In some embodiments, the hinge height 3030 atthe hinge heel end 3010 can be between 0.15 inch and 0.17 inch, 0.17inch and 0.19 inch, 0.19 inch and 0.21 inch, 0.21 inch and 0.23 inch,0.23 inch and 0.25 inch, 0.25 inch and 0.27 inch, or 0.27 inch and 0.28inch. The hinge height 3030 can increase linearly from the hinge heelend 3010 to the hinge toe end 3012. In other embodiments, the hingeheight 3030 may vary non-linearly. The hinge height 3030 can be measuredat the hinge heel end 3010, the hinge toe end 3012, or at the hingecenter 3018. Wherein the hinge center 3018 is located within the hingeand in line with the geometric face center.

B. Bending Notch

As discussed briefly above, the club head 300 of the present disclosurecan further comprise an internal bending notch 3100 that furtherincreases the dynamic loft of the club head 300 at impact. The internalbending notch 3100 influences rotational bending of the rear wall upperportion 380 about the sole 312. FIG. 19 illustrates a front view of theinterior cavity 314 of a club head 300 comprising a bending notch 3100located in the toe end 308 of the golf club head 300. The internalbending notch 3100 can remove a region of material from the toe portionof the rear body 330. In many embodiments, such as the embodiment ofFIG. 19 , the internal bending notch 3100 is located approximatelymidway between the top rail 310 and sole to increase bending and energystorage potential of the golf club head 300.

Like the flexure hinge 3000, the bending notch 3100 creates a region ofthe club head 300 that is structurally weakened to promote bending ofthe rear wall 340 to increase the club head dynamic loft. The internalbending notch 3100 allows the rear wall upper portion 380 to bendrearward at impact to increase dynamic loft and elastic energy storage,providing higher ball speeds and an increased launch angle.

In many embodiments, the location of the bending notch 3100 cancorrespond to the location of the flexure hinge 3000. For example, inembodiments wherein the internal bending notch 3100 is located withinthe rear body toe portion 336, the internal bending notch 3100 can alignwith the location of the hinge toe end 3012. The bending notch 3100 andthe flexure hinge 3000 can be located at corresponding locations suchthat the hinge toe end 3012 forms the exterior of the rear wall 340 atsubstantially the same location that the internal bending notch 3100 ispositioned within the hollow interior cavity 314. Internal bending notch3100 and the flexure hinge 3000 at corresponding locations allows theeffects of each on the club head dynamic loft to be compounded.

Referring to FIG. 19 , the bending notch 3100 can comprise a bendingnotch height 3110 measured as a percentage a height of the club head 300measured from the sole 312 to the top rail 310. In the illustratedembodiment, the bending notch height 3110 is between approximately 8% toapproximately 15% of the height of the club head 300 measured in a toprail-to-sole direction. For example, the bending notch height 3110 canbe 8%, 9%, 10%, 11%, 12%, 13%, 14%, or 15% the club head height. In someembodiments, the bending notch height 3110 can range from 0.78 inch to0.96 inch. For example, the bending notch height 3110 can beapproximately 0.78 inch, 0.79 inch, 0.80 inch, 0.81 inch, 0.82 inch,0.83 inch, 0.84 inch, 0.85 inch, 0.86 inch, 0.87 inch, 0.88 inch, 0.89inch, 0.90 inch, 0.91 inch, 0.92 inch, 0.93 inch, 0.94 inch, 0.95 inch,or 0.96 inch. In some embodiments, the bending notch height 3110 canrange from 0.78 inch to 0.80 inch, 0.80 inch to 0.82 inch, 0.82 inch to0.84 inch, 0.84 inch to 0.86 inch, 0.86 inch to 0.88 inch, 0.88 inch to0.90 inch, 0.90 inch to 0.92 inch, 0.92 inch to 0.94 inch, or 0.94 inchto 0.96 inch.

Together, the flexure hinge 3000 and bending notch 3100 provide the clubhead 300 with both an internal and external structure that areconfigured for an increase in dynamic loft and elastic energy storage.Specifically, the flexure hinge 3000 allows the club head 300 to bendover the entire length of the club head 300 in the heel to toe directionregardless of the impact location. Further, the internal bending notch3100 increases flexure in the rear body toe portion 336, where asignificant amount of the club head mass is located.

Club head 300 comprising both the flexure hinge 3000 and the bendingnotch 3100 can increase the dynamic loft of the club head 300 at impactby at least 0.5 degrees in comparison to a similar club head devoid of aflexure hinge and internal bending notch. In some embodiments, thedynamic lofting features can increase the dynamic loft of the club head300 at impact by more than 0.25 degrees, more than 0.30 degrees, morethan 0.35 degrees, more than 0.40 degrees, more than 0.45 degrees, morethan 0.50 degrees, more than 0.55 degrees, more than 0.60 degrees, morethan 0.65 degrees, more than 0.70 degrees, more than 0.75 degrees, morethan 0.80 degrees, more than 0.85 degrees, more than 0.90 degrees, morethan 0.95 degrees, or more than 1.00 degree. Such an increase in dynamicloft provides increased launch angle without sacrificing ball speed. Insome embodiments, the dynamic lofting features can increase the dynamicloft of the club head 300 at impact between 0.25 degrees and 0.30degrees, 0.30 degrees and 0.35 degrees, 0.35 degrees and 0.40 degrees,0.40 degrees and 0.45 degrees, 0.45 degrees and 0.50 degrees, 0.50degrees and 0.55 degrees, 0.55 degrees and 0.60 degrees, 0.60 degreesand 0.65 degrees, 0.65 degrees and 0.70 degrees, 0.70 degrees and 0.75degrees, 0.75 degrees and 0.80 degrees, 0.80 degrees and 0.85 degrees,0.85 degrees and 0.90 degrees, 0.90 degrees and 0.90 degrees, or 0.95degrees and 1.00 degrees. The increase in dynamic loft increases theamount of spring energy stored in the club head 300.

The flexure hinge 3000 and/or bending notch 3100 can be combined withany of the various L-shaped faceplate 150 geometries described aboveincluding a sole return 154, a toe extension 168, a top rail extension170, or any combination thereof. The flexure hinge 3000 and/or bendingnotch 3100 can also be combined with rear body 130 geometry or featuredescribed either above or below, including a sole ledge 148, an angledweight pad 1000, a weight pad 2000 comprising an extension 2050, a heelmass 147 and/or toes mass 149, a lower interior undercut 190, an upperinterior undercut 195, a rear exterior cavity 198, an external flexurehinge 3000, an internal bending notch 3100, an internal welding rib 179,or any combination thereof.

V. Other Features

A. Filled Interior Cavity

In many embodiments, the hollow interior cavity 114 of the club head 100according to the above embodiments comprising an L-shaped faceplate 150,dynamic lofting features, a rear wall 140 with a rear exterior cavity198, or any combination thereof can further comprise a filler material403 to damp vibrations occurring at impact and improve the sound andfeel characteristics of the club head 100. Referring to FIG. 21 , thefiller material 403 can be disposed or applied to the interior cavity114 of the club head 100. In some embodiments, the filler material 403can be applied as a paint to the entire interior surface or selectedlocations of the interior surface. In other embodiments, the fillermaterial 403 can be injected into the interior cavity 114, for example,but not limited to, through a weight port 175 or an opening that allowsaccess to the interior surface of the club head 100 to fill a volumepercentage of the interior cavity 114, as illustrated in FIG. 20 . Insome embodiments, the filler material 403 can fill substantially theentire interior cavity 114.

The filler material 403 can be disposed within the interior cavity 114.In some embodiments, the interior cavity 114 can be fully filled withthe filler material 403. In other embodiments, the interior cavity 114can be partially filled with the filler material 403. The fillermaterial 403 can be disposed on any interior surface of the club head100 that defines or resides within the interior cavity 114. The fillermaterial 403 can be disposed on the strike face back surface 156, thesole return interior surface 161, the interior surface of the top rail110, the interior surface of the rear body heel portion, the interiorsurface of the rear wall 140, one or more surfaces of the weight pad1000, the interior surface of the sole return 154, or any combinationthereof.

The filler material 403 can fill part of the interior cavity 114. Insome embodiments, the filler material 403 fills substantially the entirevolume of the interior cavity 114. In some embodiments the fillermaterial 403 can fill greater than 5%, greater than 10%, greater than20%, greater than 30%, greater than 40%, greater than 50%, greater than60%, greater than 70%, greater than 80%, or greater than 90% of thevolume of the interior cavity 114. In other embodiments, the fillermaterial 403 can fill less than 90%, less than 80%, less than 70%, lessthan 60%, less than 50%, less than 40%, less than 30%, less than 20%,less than 10%, or less than 5% of the volume of the interior cavity 114.In other embodiments the filler material can fill between 5% and 10%,10% and 20%, 20% and 30%, 30% and 40%, 40% and 50%, 50% and 60%, 60% and70%, 70% and 80%, 80% and 90%, 90% and 100%, 5% and 20%, 10% and 30%,20% and 40%, 30% and 50%, 40% and 60%, 50% and 70%, 60% and 80%, 70% and90%, or 90% and 100%. The amount of filler material 403 can be selectedto provide acoustic and/or performance benefits to the club head 100.

In some embodiments, the filler material 403 can be disposed on thestrike face back surface 156. In some embodiments, the filler material403 can be disposed on the entire strike face back surface 156. In otherembodiments, the filler material 403 can be disposed on only a portionof the strike face back surface 156, such as a top region located nearthe top rail 110, a bottom region located near the sole 112, a toeregion located near the toe end 108, a heel region located near the heelend 106, a center region located near the center of the strike face 116,or any combination thereof. In some embodiments, the filler material 403can cover the entire strike face back surface 156. In other embodiments,the filler material 403 can cover greater than 5%, greater than 10%,greater than 20%, greater than 30%, greater than 40%, greater than 50%,greater than 60%, greater than 70%, greater than 80%, or greater than90% of the strike face back surface 156. In other embodiments, thefiller material 403 can cover less than 90%, less than 80%, less than70%, less than 60%, less than 50%, less than 40%, less than 30%, lessthan 20%, less than 10%, or less than 5% of the strike face back surface156. In other embodiments the filler material can cover between 5% and10%, 10% and 20%, 20% and 30%, 30% and 40%, 40% and 50%, 50% and 60%,60% and 70%, 70% and 80%, 80% and 90%, 90% and 100%, 5% and 20%, 10% and30%, 20% and 40%, 30% and 50%, 40% and 60%, 50% and 70%, 60% and 80%,70% and 90%, or 90% and 100%. The amount of filler material 403 coverageon the strike face back surface 156 can be selected to provide acousticand/or performance benefits to the club head 100.

As described above, the filler material 403 can be injected into theinterior cavity 114 via a weight port 175. In many embodiments, asillustrated by FIG. 21 , the club head 100 comprises a weight port 175located on the toe portion of the rear body 130 (i.e., on the peripheryof the club head 100). The weight port 175 can form an opening theprovides access to the interior cavity 114. After welding of the rearbody 130 and the faceplate 150, the filler material 403 can be injectedthrough the opening formed by the weight port 175. The interior cavity114 can then be sealed off by coupling a weight member 176 within theweight port 175 and closing off the opening. In many embodiments, theweight member 176 and the weight port 175 are correspondingly threadedto allow for convenient and secure coupling of the weight member 176within the weight port 175.

In many embodiments, the filler material 403 is a polymer. The polymercan comprise a thermoplastic, a thermoplastic elastomer, polyurethane,ethylene, vinyl acetate, ethylene vinyl acetate (EVA), polyolefincopolymer, styrene, styrene-butadiene, any other suitable polymermaterial, or any combination thereof. In other embodiments, the fillermaterial 403 can comprise an elastomer, a polyurethane elastomer, asilicone, a silicone elastomer, a rubber, or a vulcanized natural rubberlatex. In other embodiments still, the filler material 403 can be anepoxy, a resin, an adhesive, a polyurethane adhesive, a glue, or anyother suitable adhesive. For example, the filler material 403 can be apolyurethane adhesive such as Gorilla Glue (Gorilla Glue Company,Cincinnati Ohio). In another example, the filler material 403 can be apolyurethane elastomer such as Freeman 1040 (Freeman Manufacturing &Supply Company, Avon Ohio), or a polyurethane based thermoplasticelastomer such as Freeman 3040 (Freeman Manufacturing & Supply Company,Avon Ohio).

The filler material 403 can be useful in attenuating vibrations thatoccur in the club head 100 at impact with a golf ball. The inclusion ofthe filler material 403 can damp (i.e., reduce the amplitude of)dominant vibrations that contribute to undesirable sound or feel. Insome embodiments, the filler material 403 can be located at targetedlocations corresponding to the location of dominant vibrations in orderto efficiently damp such vibrations. The damping of vibrations in theclub head 100 by inclusion of the filler material 403 creates a quieter,shorter sound at impact that is more pleasing to the human ear, as wellas a soft feel that is comfortable for the player swinging the golfclub.

In some embodiments, in addition to providing vibration dampingbenefits, the filler material 403 can also contribute to increasedperformance. For example, in some embodiments, the filler material 403can comprise desirable rebounding properties that create a spring effecton the strike face back surface 156 at impact. The spring effect createdby the filler material 403 can lead to increased energy transfer betweenthe strike face 116 and the golf ball, leading to higher ball speeds andgreater shot distances.

In some embodiments, the filler material 403 can provide reinforcementto the back of the strike face 116 or any other portion of the club head100. The filler material 403 can allow the strike face 116 or otherportions of the club head 100 to be thinned without sacrificingstructural integrity. Combining a thinner strike face 116 with therebounding properties of the filler material 403 allows for increasedflexure in the faceplate 150 with greater “bounce back” at impact,thereby increasing energy transfer and ball speed.

In many embodiments, it is desirable for the filler material 403 to belightweight (i.e., comprise a low density and low mass in relation tothe overall mass of the club head 100). The lightweight filler material403 can provide vibration damping benefits to the club head 100 toimprove sound and feel, while affecting the mass properties of the clubhead 100 that influence performance (i.e., MOI and CG position) anegligible amount. The mass of the filler material 403 can be less than20 grams so as to not negatively impact the mass properties of the clubhead 100. In some embodiments, the filler material 403 comprises a massless than 18 grams, less than 16 grams, less than 14 grams, less than 12grams, less than 10 grams, less than 8 grams, less than 6 grams, lessthan 4 grams, less than 2 grams, or less than 1 gram. In someembodiments, the filler material 403 comprises a mass between 1 gram and5 grams, between 5 grams and 10 grams, between 10 grams and 15 grams, orbetween 15 grams and 20 grams. In some embodiments, the mass of thefiller material 403 can be 1, 2, 3, 4, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5,9, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 13, 14, 15, 16, 17, 18, 19, or 20grams. The mass of the filler material 403 can be selected to provide alow density and low mass filler material 403 that provides acousticand/or performance benefits to the club head 100.

As discussed above, the combination of any of the L-shaped faceplategeometries described above including a sole return, a toe extension, atop rail extension, or any combination with any of the various rear bodyfeatures or geometries described herein including a sole ledge, anangled weight pad, a weight pad comprising an extension, a heel massand/or toes mass, a lower interior undercut, an upper interior undercut,a rear exterior cavity, an external flexure hinge, an internal bendingnotch, an internal welding rib, filler material or any combinationthereof result in a high performance club head. The combination of thevarious features listed above produces a club head with high amounts offlexure and increased internal energy at impact, resulting in increasedball speeds.

D. Rear Ribs

FIGS. 22-24 illustrate another exemplary embodiment according to aspectsof the present invention. In this embodiment, the golf club head 500comprises many of the features described above such as a weight pad5000, sole return, filler material, and thin walls. Together, and asmentioned above, these features provide optimal mass placement whiledynamically lofting the strike face 516. In the illustrated embodiment,the golf club head 500 further comprises a plurality of ribs 511 locatedon the interior surface of the rear wall 540. The ribs 511 work inconjunction with the above-mentioned features to further provideimproved frequency and sound response of the club head 500 upon impactwith a golf ball.

The interior surface of the rear wall 540 internal cavity comprises aplurality of ribs 511. The plurality of ribs 511 extends in a directionfrom the top rail 510 toward the sole 512. The plurality of ribs 511 canbe located anywhere on the interior surface of the rear wall 540. Insome examples, the plurality of ribs 511 can be positioned onto aportion of the interior surface of the lower exterior wall 545. In otherexamples, the plurality of ribs 511 can be positioned on a portion ofthe rear wall 540 interior surface. In some embodiments, the pluralityof ribs 511 can be positioned on a portion of the interior surface ofthe lower exterior wall 545 and can extend into another portion of therear wall 540. The plurality of ribs 511 can comprise between one toeight ribs. For example, the plurality of ribs 511 can comprise one rib,two ribs, three ribs, four ribs, five ribs, six ribs, seven ribs, oreight ribs. In embodiments having one or more plurality of ribs 511, theplurality of ribs 511 can be spaced equidistance from each other or moreconcentrated near the heel region, toe region, top rail, or sole. Theplurality of ribs 511 and the location of the plurality of ribs 511 canhelp optimize the frequency and amplitude of sound response.

The rear wall thickness, as discussed above, can be manipulated with theinclusion of the plurality of ribs 511. Specifically, providing aplurality of ribs 511 along the interior surface of the rear wall 540allows the surrounding rear wall 540 to have a reduced thickness, whichcreates more club head 500 flexibility and improves ball speed, whilemaintaining golf club head 500 durability. Further, a thin rear wall540, in combination with ribs, improves the frequency and amplitude ofsound response, leading to better sound and feel upon impact.

Method

The various embodiments of the golf club head described herein can bemanufactured by various methods. As discussed above, the golf club headcomprises at least a rear body and an L-shaped faceplate. Differentembodiments of each feature can be combined to form numerous variationsof the golf club head. The method of manufacture can vary for differentvariations of the golf club head. Described below are example methods ofmanufacturing the golf club head.

The method of manufacturing a golf club head comprising an L-shapedfaceplate can comprise (1) providing a rear body, (2) providing afaceplate, and (3) coupling the faceplate to the rear body, or any stepcombination provided above.

Providing the rear body can comprise forming a rear body top railportion, a sole portion, a rear body toe portion, and a rear body heelportion that define a rear body opening for receiving the faceplate. Therear body can further comprise a plurality of welding surfaces thatextend around a perimeter of the rear body opening and provide aninterface for the faceplate and the rear body to be coupled together.The rear body can further comprise a sole ledge for receiving the solereturn. In some embodiments, the rear body can further comprise a weightpad that projects forward from the sole portion. In some embodiments,the rear body can further comprise one or more dynamic lofting features.In providing the rear body, the portions of the rear body can beintegrally cast.

Providing the faceplate can comprise forming a strike face portion and asole return that wraps around the leading edge to form a portion of thesole. The faceplate can comprise a toe extension and a top railextension. In providing that faceplate, the faceplate can be formed by amachining and forming process.

Coupling the faceplate to the rear body can comprise connecting thefaceplate to the rear body at the welding surfaces. The sole ledge canreceive the sole return, and the weight pad can overhang a portion ofthe sole return. The faceplate can be welded to the rear body at thewelding surfaces. Forming the rear body and the faceplate separately canallow the rear body and the faceplate to be formed from differentmaterials. Further, forming the rear body and the faceplate separatelycan allow the rear body and the faceplate to be formed using differentmethods. For example, the rear body can be cast, and the faceplate canbe forged.

EXAMPLES VI. Example 1: Comparison of Faceplate Performance Results

Further described herein is a comparison of performance results betweenmultiple crossover-type club heads that had different faceplateconstructions. The results compared the effects that the faceplate sizeand shaping had on performance and durability. The leading edgecomposition, the location of the faceplate weld line, and the faceplatesurface area were varied throughout the exemplary club heads. Asdiscussed above, the leading edge of the club head is a high-stressregion that is typically formed from a rigid material. The resultsdemonstrated the effects of forming the leading edge from ahigh-strength material rather than the rear body material. Further, theweld line limits the ability of the faceplate to flex. The resultsfurther demonstrated the effects of moving the weld line closer to theclub head periphery, in comparison to a traditional club head. Thefaceplate surface area correlates to the spring-like effect of thefaceplate. The results further demonstrated the effects of increasingthe faceplate surface area. The faceplate constructions of the clubheads are described in further detail below.

A. First Exemplary Club Head

The first exemplary club head comprised an L-shaped faceplate (hereafterreferred to as “the first example faceplate”) that formed the entirestriking surface. The first example faceplate comprised a sole return, atoe extension, and a top rail extension, similar to club head 100 shownin FIG. 1A. The first example faceplate extended to the periphery of theclub head and formed a portion of the sole. Therefore, the leading edgewas formed from the first example faceplate material. The weld line waslocated near the periphery of the club head. The first example faceplatewas laser welded to the rear body. The first exemplary club headcomprised a negligible amount of filler material. The first control clubhead comprised a faceplate that had both a different geometry and adifferent weld type.

The first control club head comprised a faceplate (hereafter referred toas “the first control faceplate”) that did not form the entire strikingsurface, nor a portion of the sole. The first control faceplate wasdevoid of a sole return, a toe extension, and a top rail extension. Thefirst control faceplate did not extend to the club head periphery anddid not form a portion of the sole. Instead, the first control club headincluded a stepped-transition region at the leading edge of the clubhead. Therefore, the leading edge was formed from the rear bodymaterial. The weld line was located around the perimeter of the strikeface. The first control faceplate was plasma welded to the rear body.The first control faceplate represented a traditional faceplate insert,where the faceplate does not form a portion of the sole.

The first control faceplate differed in geometry from the first examplefaceplate, in which the faceplate included a sole return. The firstexample faceplate had a larger surface area than the first controlfaceplate. The first exemplary club head had a leading edge formed fromthe first example faceplate material, and the first control club headhad a faceplate formed from the main body material. The first examplefaceplate exemplified performance and durability benefits over the firstcontrol faceplate, as discussed in further detail below.

1. Performance Testing

The performance tests measured the ball speeds, launch angles, spinrates, and carry distance of each faceplate. An automated performancetest used a golf swing apparatus to capture performance data of the clubhead under regular conditions. The results indicated the performance ofeach faceplate near a low-center region, located just below the centerof the faceplate.

The first exemplary club head demonstrated improved performance benefitsover the first control club head. The comparison between these two clubheads exemplified the impact of increasing the faceplate surface area asforming the leading edge from the faceplate material. The firstexemplary club head had a faceplate including a sole return and a largerfaceplate surface area, in comparison to the first control club head.Table 1 below indicates the performance improvements of the firstexemplary club head over the first control club head. Ball speed wasmeasured in miles per hour, the carry distance was modeled in yards.

TABLE 1 First Control First Exemplary Club Head Club Head DifferenceConstruction Faceplate insert, Faceplate — no sole return, no includedtoe extension, a toe extension, a no top rail top rail extension,extension and a sole return Surface Area (in²) 2.74 5.23 +2.49 in² BallSpeed (mph) 133.7 136.4 +2.7 mph Carry Distance (yds) 216.7 218.4 +1.7yds

Referring to Table 1 above, the first exemplary club head demonstratedimprovements over the first control club head on low-center hits. Thefirst control club head demonstrated ball speeds off low-center hits of133.7 mph, while the first exemplary club head demonstrated ball speedsoff low-center hits of 136.4 mph. The first exemplary club headincreased ball speed on low-center hits by 2.7 mph, compared to thefirst control club head. The increase in ball speed translated to anadditional 1.7 yards of carry distance. The results from the automatedperformance test were reinforced by the results from a playerperformance test, which captured data from shots by actual players. Theresults of the player performance test are indicated in Table 2 below.

TABLE 2 Control First Exemplary Club Club Head Head Difference BallSpeed Hits (mph) 137.3 139.3 +2

Referring to Table 2 above, the results from the player performance testfurther demonstrate the improvement of the first exemplary club headover the first control club head. The first exemplary club headincreased ball speed by 2 mph, compared to the first control club head.

The performance improvements of the first exemplary club head, asindicated above, were attributed to the faceplate geometry. The solereturn was formed from the first example faceplate material, whichallowed the leading edge (or low-center region) to be thinner and moreflexible. The sole return allows increased flexing near the leading edgeof the faceplate. The faceplate also had a larger surface area than thecontrol faceplate as it extended to the top rail and toe side periphery.The first example faceplate was 2.49 in² lager than the first controlfaceplate. The increased faceplate surface are required the weld line tobe moved further toward the rear body. The weld line can inhibitflexing, so moving the weld line closer to the rear body furtherincreased faceplate flexure.

The first example faceplate material comprised a higher strength thanthe rear body material. The increased flexing exaggerated thespring-like effect of the first example faceplate, thereby transferringmore energy from the faceplate to the golf ball. Therefore, thecombination of the sole return and the extended perimeter allowed thefirst example faceplate to flex more, which produced faster ball speeds.The first example faceplate material was also stronger than the rearbody material. As a result, the first example faceplate constructionalso improved the durability of the first exemplary club head, asdiscussed in further detail in the durability testing section below.

2. Durability Testing

The durability test measured the number of hits that the club headscould withstand before failure. In the durability test, the club headswere subject to high velocity golf ball impacts by using an air cannonapparatus. Table 3 below indicates the results of the durability test.Three samples of each club head type were tested. The data from thethree samples of the “first exemplary club heads” and the three samplesof the “first control club heads” was then averaged. The “Hits UntilFailure” row indicates the average number of golf ball impacts that eachclub head experienced before failure. The “Minimum Hits Until Failure”row indicates the worst-performing sample of each club head type whichexperienced the minimum number of impacts before failure. All values inTable 3 are in number of golf balls.

TABLE 3 First Control First Exemplary Percent Club Head Club HeadDifference Change Average Hits 1584.2 2564 +979.8  61.8% Until FailureMinimum Hits 1000 2292 +1292 129.2% Until Failure

Referring to Table 3 above, the first exemplary club head demonstrated asignificant increase in durability. The first control club head was ableto withstand an average of 1584.2 hits, while the first exemplary clubhead was able to withstand an average of 2564 hits. On average, thefirst exemplary club head withstood 61.8% more hits than the firstcontrol club head. The first control club head experienced a minimum of1000 hits before failure, while the first exemplary club headexperienced a minimum of 2292 hits before failure. The worst performingsample of the first exemplary club head experienced 129.2% more hitsthan the worst performing sample of the first control club head. Golfclub head failure is commonly observed near the club head leading edge.The durability improvements demonstrated by the first exemplary clubhead were attributed to the sole return, which placed a high-strengthmaterial near the leading edge.

B. Second Exemplary Club Head

The second exemplary club head comprised an L-shaped faceplate(hereafter referred to as “the second example faceplate”) that did notform the entire striking surface. The second example faceplate compriseda sole return but was devoid of a toe extension, and a top railextension, similar to the club head shown in FIG. 8 . Therefore, thesecond example faceplate formed a portion of the sole (the leading edgewas formed from the faceplate material), but the faceplate did notextend all the way to the club head periphery on the toe end and/or thetop rail. The weld line was located around the perimeter of the strikeface. The second example faceplate was plasma welded to the rear body.The second exemplary club head comprised a negligible amount of fillermaterial. The second example faceplate was similar to the first examplefaceplate from Example 1, but for the difference in surface area and thetype of weld that was used to secure the second example faceplate to therear body.

The second control club head was similar to the first control club headfrom Example 1. The second control club head comprised a faceplate(hereafter referred to as “the second control faceplate”) that did notform the entire striking surface, nor a portion of the sole. The secondcontrol club head represented a club head that comprised a traditionalfaceplate insert.

The second control faceplate differed in geometry from the secondexample faceplate, in which the faceplate included a sole return.Further, the second example faceplate had a larger surface area than thesecond control faceplate. The second exemplary club head had a leadingedge formed from the second example faceplate material, and the secondcontrol club head had a faceplate formed from the main body material.The second example faceplate exemplified performance and durabilitybenefits over the second control faceplate, as discussed in furtherdetail below.

3. Performance Testing

The performance test was conducted similarly to the performance test ofExample 1. The second exemplary club head demonstrated improvedperformance benefits over the second control club head. Similar toExample 1, the comparison between the second exemplary club head and thesecond control club head exemplified the impact of increasing thesurface area of the faceplate as well as forming the leading edge fromthe faceplate material. Table 4 below indicates the performanceimprovements of the second exemplary club head over the second controlclub head. Ball speed was measured in miles per hour, the carry distancewas modeled in yards.

TABLE 4 Second Control Club Head Second Exemplary Club Head DifferenceConstruction Faceplate insert, no sole return, no Faceplate included asole return, — toe extension, no top rail no toe extension, no top railextension extension Surface Area (in²) 2.74 3.99 +1.25 Ball Speed (mph)131.1 132.1 +1.0 mph Carry Distance (yds) 213.9 215.6 +1.7 yds

Referring to Table 4 above, the second exemplary club head demonstratedimprovements over the second control club head on low-center hits. Thesecond control club head demonstrated ball speeds on low center hits of131.1 mph, while the second exemplary club head demonstrated ball speedsoff low center hits of 132.1 mph. The second exemplary club headincreased ball speed on low-center hits by 1 mph, compared to the secondcontrol club head. The increase in ball speed translated to anadditional 1.7 yards of carry distance.

The performance improvements of the second exemplary club head, asindicated above, are attributed to the faceplate geometry. Similar tothe first exemplary club head from Example 1, the sole return of thesecond exemplary club head was formed from the second example faceplatematerial which allowed the leading edge (or low-center region) to bethinner and more flexible. The surface area of second example faceplatewas 1.25 in t larger than the second control faceplate. The combinationof the sole return and the larger strike face increased flexure in thefaceplate, thereby increasing ball speed and carry distance. The secondexample faceplate material was also stronger than the rear bodymaterial. As a result, the second example faceplate construction alsoimproved the durability of the second exemplary club head, as discussedin further detail in the durability testing section below.

4. Durability Testing

Table 5 below indicates the results of the durability test. Similar toExample 1, three samples of each club head type were tested. The datafrom the three samples of the “second exemplary club heads” and thethree samples of the “first control club heads” was then averaged. The“Hits Until Failure” row indicates the average number of golf ballimpacts that each club head experienced before failure. The “MinimumHits Until Failure” row indicates the worst-performing sample of eachclub head type which experienced the minimum number of impacts beforefailure. All values in Table 5 are in number of golf balls.

TABLE 5 Second Second Control Exemplary Percent Club Head Club HeadDifference Change Average Hits Until Failure 1584.2 2307.7 +723.5 45.6%Minimum Hits Until Failure 1000 2000 +1000  100%

Referring to Table 5 above, the second exemplary club head demonstrateda significant increase in durability. The second control club head wasable to withstand an average of 1584.2 hits, while the second exemplaryclub head was able to withstand an average of 2307.7 hits. On average,the second exemplary club head withstood 45.6% more hits than the secondcontrol club head. The second control club head experienced a minimum of1000 hits before failure, while the second exemplary club headexperienced a minimum of 2000 hits before failure. The worst performingsample of the second exemplary club head experienced 129.2% more hitsthan the worst performing sample of the second control club head. Golfclub head failure is commonly observed near the club head leading edge.The durability improvements demonstrated by the second exemplary clubhead were attributed to the sole return, which placed a high-strengthmaterial near the leading edge.

The first and second exemplary club heads increased ball speed and carrydistance over their respective control club heads. Further, the firstexemplary club head increased ball speed and carry distance over thesecond exemplary club head. The exemplary club heads also demonstrated asimilar improvement to durability over their respective control clubheads. Notwithstanding test conditions and the type of weld used tosecure the faceplate, the exemplary club heads demonstrated improvedperformance and durability. Therefore, it is apparent that the faceplatehaving the sole return and larger surface area improves performance incomparison to a similar club head devoid of a sole return.

VII. Example 2: Finite Element Analysis (FEA)

Further described herein is a comparison of a finite element analysisperformed on two crossover-type club heads having different sole ledgegeometries. The finite element analysis (FEA) simulated the ball speedsof each club head given their different constructions. As discussedabove, the sole ledge is located immediately forward of the weight padand forms a portion of the sole. The sole ledge provides a surface forthe faceplate to easily be attached to the rear body. The purpose of theFEA comparison was to demonstrate the similar performance of a golf clubhead comprising a sole ledge over a golf club head devoid of a soleledge. Further, the discussion below illustrates the ease ofmanufacturing provided by a club head that includes a sole ledge.

The sample club heads included similar faceplates, similar to theL-shaped faceplate illustrated in FIG. 6 . The faceplates included asole return, a toe extension, and top rail extension. Further, the solereturn depth was the same in each sample club head. The sample clubheads also included a similar center of gravity (CG) location. Toachieve a similar CG location in the control club head, mass was addednear the top rail on the toe end of the club head. The faceplateconstruction and CG location were kept constant to isolate thedifference in performance caused by the different sole ledgeconstructions.

The control club head comprised a rear body having an overhanging weightpad similar to the weight pad illustrated in FIG. 12 . The weight padincluded a projection that extended toward the faceplate and overhungthe sole return. The control club head was devoid of a sole ledge.Instead, the sole return extended into the weight pad such that theweight pad overlapped the rearmost portion of the sole return. Thefaceplate sole perimeter edge and a portion of the faceplate interiorsurface contacted the weight pad. The weight pad formed an upper andrear boundary of the sole return.

The exemplary club head comprised a rear body having an overhangingweight pad similar to the weight pad illustrated in FIG. 10 . Theoverhanging weight pad was angled with respect to the sole and overhungthe sole return. The rear body further comprised a sole ledge similar tothe sole ledge illustrated in FIG. 13 , where the sole ledge frontsurface received the faceplate sole perimeter edge. Further, the weightpad did not contact the sole return and did not form an upper boundaryof the sole return. The sole ledge comprised a similar thickness to thesole return.

The control and exemplary club heads included different weight pad andsole ledge constructions. The control club head included a weight padwith a projection, and the exemplary club head included an angled weightpad. The control club head did not include a sole ledge, and the weightpad contacted the sole return of the faceplate. In contrast, theexemplary club head included a sole ledge that prevented the weight padfrom contacting the sole return of the faceplate. In comparison to theexemplary club head, the effective depth of the sole return of thecontrol club head was decreased by the depth of the weight pad thatoverlapped the sole return. The results discussed below compare theeffects that the sole ledge geometry had on performance.

The FEA analysis simulated the internal energy of the sample club heads(measured in pound-force inch). The internal energy was the amount ofelastic energy stored and released in the club head by a golf ballimpacting and bending the strike face. The difference in ball speed(measured in miles per hour) was derived from the difference in internalenergy. The sample club heads were tested at a swing speed of 85 mph tosimulate real-world swing conditions. The results indicated theperformance of each faceplate near a center of the faceplate.

TABLE 6 Control Club Head Exemplary Club Head Internal Energy (lbf-in)55.82 56.21

Referring to Table 6 above, the control club head demonstrated aninternal energy of 55.82 lbf-in, and the exemplary club headdemonstrated an internal energy of 56.21 lbf-in. The exemplary club headincreased internal energy by 0.39 lbf-in over the control club head,which translated to a 0.05 mph increase in ball speed. The control andexemplary club heads performed similarly.

Although the control and exemplary club heads performed similarly, theexemplary club head provided manufacturing advantages over the controlclub head. The exemplary club head did not lose performance over thecontrol club head, and the exemplar club head is cheaper and easier tomanufacture than the control club head. As discussed above, theexemplary club head included a sole ledge that received the soleperimeter edge of the faceplate. The control club head did not include asole ledge, and instead, the weight pad received the faceplate near thesole. The exemplary club head required only a single surface of the solereturn (the sole perimeter edge) to be attached to the sole ledge. Incontrast, the control club required two surfaces of the sole return beattached to the rear body (the sole perimeter edge and a portion of theinterior surface). Therefore, the rear body of the control club headrequired that two surfaces were prepared to receive the sole returnversus the exemplary club head, which only required one surface to beprepared. The preparation of additional surfaces added steps to themanufacturing process, which increased the cost of manufacturing thecontrol club head.

Further, the control club head included a more complex receivinggeometry than the exemplary club head. Each club head has a margin oferror at the interface of the sole return and the rear body. The soleledge allowed for a larger margin of error when aligning the sole returnwith the rear body because only one surface of the sole return mustalign with the rear body. In contrast, the control club head requiredtwo surfaces of the sole return to align with the rear body. Therefore,the control club head required a more precise fit between the solereturn and the rear body, which decreased the allowable margin of errorat the interface. Due to the decrease in the margin of error, thecontrol club head required that the sole return was formed withinextremely tight tolerances. Therefore, the control club head was moredifficult to manufacture than the exemplary club head.

As discussed above, the thicknesses of the sole return and sole ledgewere similar. These similar thicknesses allowed an even weld bead to beformed on either side of the faceplate it is welded to the rear body. Incontrast, the weight pad of the control club head was positioned abovethe sole return and did not allow an even weld bead to be formed.Therefore, the samples performed similarly, but the exemplary club headwas cheaper and easier to manufacture than the control club head.

VIII. Example 3: L-Cup Depth

Further described herein is comparison of a finite element analysisperformed on two crossover-type club heads having different sole returngeometries. The finite element analysis (FEA) simulated the ball speedsof each club head given their different constructions. As discussedabove, increasing the sole return depth increases the flexure of thefaceplate. Therefore, the purpose of the FEA comparison was todemonstrate the performance improvements that resulted from increasingthe sole return depth.

The control club head comprised a control L-shaped faceplate similar tothe faceplate illustrated in FIGS. 8 and 9 . The control faceplateincluded a control sole return that wrapped over the leading edge andformed a portion of the sole. The control sole return depth was 0.30inch. The control club head further comprised a control rear body havinga control sole ledge that received the control sole return.

The exemplary club head comprised an exemplary L-shaped faceplatesimilar to the control faceplate. However, the exemplary sole returndepth was 0.40 inch. The exemplary sole return depth was increased tothe manufacturing limit. The exemplary sole return depth was 33% longerthan the control return depth. The exemplary club head further comprisedan exemplary rear body having an exemplary sole ledge that received theexemplary sole return.

The control and exemplary club heads comprised rear body constructionssimilar to the club head illustrated in FIG. 9 . However, the controlsole ledge was longer than the exemplary sole ledge to accommodate theshortened control sole return. The remaining portions of the control andexemplary rear bodies were kept similar to isolate the difference inperformance caused by lengthening the exemplary sole return.

The FEA analysis simulated the internal energy of the sample club heads(measured in pound-force inch). The internal energy was the amount ofelastic energy stored and released in the club head by a golf ballimpacting and bending the strike face. The difference in ball speed(measured in miles per hour) was derived from the difference in internalenergy. The sample club heads were tested at a swing speed of 85 mph tosimulate real-world swing conditions. The results indicated theperformance of each faceplate near a center of the faceplate, and alow-center region, located just below the center of the faceplate.

TABLE 7 Control Club Exemplary Club Head Head Center Hits InternalEnergy (lbf-in) 58.52 59.91 Low-Center Hits Internal Energy (lbf-in)46.25 47.82

Referring to Table 7 above, the exemplary club head demonstrated ahigher internal energy on both center hits and low-center hits. Oncenter hits, the control club head demonstrated an internal energy of58.52 lbf-in, and the exemplary club head demonstrated an internalenergy of 59.91 lbf-in. The exemplary club head increased internalenergy by 1.39 lbf-in over the control club head, which translated to a0.18 mph increase in ball speed on center hits.

On low-center hits, the control club head demonstrated an internalenergy of 46.25 lbf-in, and the exemplary club head demonstrated aninternal energy of 47.82 lbf-in. The exemplary club head increasedinternal energy by 1.57 lbf-in over the control club head, whichtranslated to a 0.20 mph increase in ball speed on center hits.

The results of Table 7 illustrate the difference that the sole returndepth had on increasing ball speed. As discussed in detail above,increasing the sole return depth increases the amount of rear bodymaterial replaced by faceplate material. The replacement of rear bodymaterial by faceplate material leads to an increase in the flexibilityof the sole. The lengthening of the sole return directly led to asubstantial increase in ball speed. For increased performance, it istherefore desirable to increase the depth of the sole return withinmanufacturability limits.

IX. Example 4: Weight Pad Embodiment Comparison

Further described herein is a comparison of a finite element analysisperformed on three crossover-type club heads having different weight padgeometries. The finite element analysis (FEA) simulated the durabilityand ball speeds of each club head given their different constructions.As discussed above, the combination of low CG and high flexibility inthe club head can create performance improvements such as increased ballspeed and higher launch angle. Therefore, the purpose of the FEAcomparison was to demonstrate the performance improvements that resultedfrom overhanging weight pad constructions.

TABLE 8 Control Club First Exemplary Second Exemplary Head Club HeadClub Head CG Height (inch) 0.525 0.532 0.518 Relative Angle (°) 0.680.67 0.74

The control club head comprised a control L-shaped faceplate, similar tothe faceplate illustrated in FIGS. 8 and 9 . The control club includes arear body construction similar to the club head illustrated in FIG. 18C.The rear body further comprised a sole ledge, where the sole ledge frontsurface received the faceplate sole perimeter edge. Further, the weightpad did not contact the sole return and did not form an upper boundaryof the sole return. The sole ledge comprised a similar thickness to thesole return.

The first exemplary club head comprised an L-shaped faceplate and solesimilar to that of the control club, but for the weight pad. The firstexemplary weight pad comprised a rear body construction similar to theclub head illustrated in FIG. 25 . The second exemplary club headcomprised an L-shaped faceplate and sole similar to that of the controlclub. However, the first exemplary weight pad comprised a rear bodyconstruction similar to the club head illustrated in FIG. 29 . Theresults discussed below compare the effects that the club headconstruction has on the durability and performance.

The FEA analysis simulated the internal energy (measured in pound-forceinch), relative loft angle (measured in degrees), and club head stresses(measured in ksi) of the sample club heads. The sample club heads weretested at a swing speed of 95 mph to simulate real-world swingconditions. Referring to Table 8, the weight pad construction of thesecond exemplary club head allocated more mass downward compared to thecontrol club. Lower CGy values (smaller CG height) correlates toincreases in ball speed and higher golf ball launch angle. Additionallyreferring to Table 8, the relative loft angle of the first exemplaryclub head is greater than that of the control club. Larger relative loftangle correlates to higher golf ball launch angle and ball spin values.

The FEA analysis simulation also displayed less stresses in the sole forthe first and second exemplary club heads when compared to the stressesin the sole of the control club head. Yield stress for the body is 150ksi. The stresses in the sole of the control club head were 5 ksi overthis maximum yield stress while the yield stress of the first and secondexemplary club heads were below the yield. Due to the variation inweight pad and back surface construction, the bending mechanics of thefirst and second exemplary club heads were different than the controlclub head leading to reduced stresses. This reduction in stress meansthat the sole and other walls of the club head body can be thinned tofurther increase ball performance such as ball speed and launch angle.

CLAUSES

Clause 1. An iron-type golf club head comprising: a faceplate and a rearbody forming a club head body and enclosing a hollow interior cavity; atop rail, a sole, a heel end, and a toe end, wherein: the club head bodyforms a front end, a rear end, a top rail periphery, a toe periphery, aheel periphery, and a sole periphery; the faceplate is disposed at thefront end; the faceplate comprises a strike face, a back surfaceopposite the strike face, a leading edge proximate the sole, a solereturn extending rearward from the back surface and forming at least aportion of the sole, and a faceplate perimeter, wherein: the faceplateperimeter comprises a top perimeter edge, a heel-side perimeter edge, atoe-side perimeter edge and a sole perimeter edge; the rear body formsat least a portion of the top rail, at least a portion of the sole, atleast a portion of the toe end; the rear body comprises a rear wallextending from the sole to the top rail at the rear end, a sole ledge,and a hosel structure located on the heel end; the sole ledge projectsfrom the rear body toward the faceplate and forms a portion of the sole;the top perimeter edge of the faceplate is located on the top railperiphery of the club head body, the toe-side perimeter edge of thefaceplate is located on the toe periphery of the club head body, and thesole perimeter edge of the faceplate contacts the sole ledge; thefaceplate is welded to the rear body along the faceplate perimeter; therear body further comprises a weight pad proximate the sole and the rearwall, wherein: the weight pad overhangs the sole return, and the weightpad does not contact the sole return.

Clause 2. The iron-type golf club head of clause 1, wherein the weightpad is separated from the sole return by the sole ledge.

Clause 3. The iron-type golf club head of clause 1, further comprising afaceplate surface area measured across the faceplate between the topperimeter edge, the toe-side perimeter edge, the heel-side perimeteredge, and the leading edge; wherein the faceplate surface area isbetween 5.00 in² and 6.00 in².

Clause 4. The iron-type golf club head of clause 1, wherein thefaceplate comprises a first material and the rear body comprises asecond material different than the first material.

Clause 5. The iron-type golf club head of clause 4, wherein the firstmaterial comprises a first yield strength and the second materialcomprises a second yield strength; and wherein the first yield strengthis greater than the second yield strength.

Clause 6. The iron-type golf club head of clause 5, wherein the firstyield strength of the first material is between 220 ksi and 300 ksi.

Clause 7. The iron-type golf club head of clause 1, wherein the soleledge comprises a sole ledge depth between 0.01 inch and 0.20 inch.

Clause 8. The iron-type golf club head of clause 1, wherein the solereturn defines a sole return thickness, and the sole ledge defines asole ledge thickness; and wherein the sole return thickness at the soleperimeter edge is the same as the sole ledge thickness.

Clause 9. The iron-type golf club head of clause 1, wherein the solereturn comprises a sole return depth measured in a front-to-reardirection from the leading edge to the sole perimeter edge; wherein thesole return depth is between 0.2 inches and 0.4 inches.

Clause 10. The iron-type golf club head of clause 1, wherein the soleperimeter edge is the only portion of the sole return that contacts therear body.

Clause 11. The iron-type golf club head of clause 1, wherein the toprail comprises a thickness less than 0.060 inches.

Clause 12. An iron-type golf club head comprising: a faceplate and arear body forming a club head body and enclosing a hollow interiorcavity; a top rail, a sole, a heel end, and a toe end, wherein: the clubhead body forms a front end, a rear end, a top rail periphery, a toeperiphery, a heel periphery, and a sole periphery; the faceplate isdisposed at the front end; the faceplate comprises a strike face, a backsurface opposite the strike face, a leading edge proximate the sole, asole return extending rearward from the back surface and forming atleast a portion of the sole, and a faceplate perimeter, wherein: thefaceplate perimeter comprises a top perimeter edge, a heel-sideperimeter edge, a toe-side perimeter edge and a sole perimeter edge; therear body forms at least a portion of the top rail, at least a portionof the sole, at least a portion of the toe end; the rear body comprisesa rear wall extending from the sole to the top rail at the rear end, asole ledge, and a hosel structure located on the heel end; the soleledge projects from the rear body toward the faceplate and forms aportion of the sole; the top perimeter edge of the faceplate is locatedon the top rail periphery of the club head body, the toe-side perimeteredge of the faceplate is located on the toe periphery of the club headbody, and the sole perimeter edge of the faceplate contacts the soleledge; the faceplate is welded to the rear body along the faceplateperimeter; the rear body further comprises a weight pad proximate thesole and the rear wall, wherein: the weight pad overhangs the solereturn, and the weight pad does not contact the sole return; the weightpad comprises a front wall facing the front end, a top wall facing thetop rail, and a transition region between the front wall and the topwall; and the front wall is angled with respect to the sole.

Clause 13. The iron-type golf club head of clause 12, wherein the weightpad is separated from the sole return by the sole ledge.

Clause 14. The iron-type golf club head of clause 12, wherein the soleledge comprises a sole ledge depth between 0.01 inch and 0.20 inch.

Clause 15. The iron-type golf club head of clause 12, further comprisingan acute angle measured between the front wall of the weight pad and aninterior surface of the sole return; wherein the acute angle is between30 and 80 degrees.

Clause 16. The iron-type golf club head of clause 12, further comprisinga lower interior undercut formed between the front wall of the weightpad and the sole; wherein the lower interior undercut defines a lowerinterior undercut depth measured in a front-to-rear direction betweenthe transition region and a juncture between the front wall and the soleledge; and wherein the lower interior undercut depth is greater than0.100 inch.

Clause 17. An iron-type golf club head comprising: a faceplate and arear body forming a club head body and enclosing a hollow interiorcavity; a top rail, a sole, a heel end, and a toe end, wherein: the clubhead body forms a front end, a rear end, a top rail periphery, a toeperiphery, a heel periphery, and a sole periphery; the faceplate isdisposed at the front end; the faceplate comprises a strike face, a backsurface opposite the strike face, a leading edge proximate the sole, asole return extending rearward from the back surface and forming atleast a portion of the sole, and a faceplate perimeter, wherein: thefaceplate perimeter comprises a top perimeter edge, a heel-sideperimeter edge, a toe-side perimeter edge and a sole perimeter edge; therear body forms at least a portion of the top rail, at least a portionof the sole, at least a portion of the toe end; the rear body comprisesa rear wall extending from the sole to the top rail at the rear end, asole ledge, and a hosel structure located on the heel end; the soleledge projects from the rear body toward the faceplate and forms aportion of the sole; the top perimeter edge of the faceplate is locatedon the top rail periphery of the club head body, the toe-side perimeteredge of the faceplate is located on the toe periphery of the club headbody, and the sole perimeter edge of the faceplate contacts the soleledge; the faceplate is welded to the rear body along the faceplateperimeter; the rear body further comprises a weight pad proximate thesole and the rear wall, wherein: the weight pad overhangs the solereturn, and the weight pad does not contact the sole return; the weightpad comprises a weight pad extension protruding forward from a frontwall of the weight pad toward the faceplate and overhanging the solereturn.

Clause 18. The iron-type golf club head of clause 17, wherein the weightpad is separated from the sole return by the sole ledge.

Clause 19. The iron-type golf club head of clause 17, wherein the weightpad extension comprises a forward edge and a lower surface disposedtoward the sole; wherein a lower interior undercut is formed between thelower surface and an interior surface of the sole.

Clause 20. The iron-type golf club head of clause 19, wherein the lowerinterior undercut comprises a lower interior undercut depth measuredfrom the forward edge of the weight pad extension to the front wall ofthe weight pad; wherein the lower interior undercut depth is greaterthan 0.100 inch.

Clause 21: An iron-type golf club head comprising: a faceplate, a rearbody coupled to the faceplate to form a club head body enclosing ahollow interior cavity, the club head body defining a top rail, a sole,a heel end, a toe end, a front end, a rear end, a top rail periphery, atoe periphery, a heel periphery, and a sole periphery; the faceplatebeing disposed at the front end and comprising a strike face, a backsurface opposite the strike face, a leading edge proximate the sole, asole return extending rearward from the back surface and forming atleast a portion of the sole, and a faceplate perimeter; the faceplateperimeter comprising a top perimeter edge, a heel-side perimeter edge, atoe-side perimeter edge and a sole perimeter edge; the rear body beingcoupled to the faceplate along the faceplate perimeter and including: arear body top rail portion coupled to the top perimeter edge of thefaceplate perimeter and forming at least a portion of the top rail; arear body sole portion including a sole ledge coupled to the soleperimeter edge of the faceplate perimeter and forming at least a portionof the sole; a rear body heel portion coupled to the heel-side perimeteredge of the faceplate perimeter and forming at least a portion of theheel end, the rear body heel portion including a hosel; a rear body toeportion coupled to the toe-side perimeter edge of the faceplateperimeter and forming at least a portion of the toe end; a rear wallextending from the rear body sole portion to the rear body top railportion, and between the rear body heel portion to the heel body toeportion, to enclose the rear end of the club head, the rear wallcomprising: a rear wall upper portion comprising: a rear wall upperportion exterior surface; and a rear wall upper portion interiorsurface; wherein a rear wall upper portion thickness between the rearwall upper portion exterior surfaced and the rear wall upper portioninterior surface is substantially uniform; a rear wall lower portioncomprising a rear wall lower portion exterior surface; a rear wall lowerportion interior surface; a weight pad formed between the rear walllower portion exterior surface and the rear wall lower portion interiorsurface and located proximate the sole, the weight pad comprising: aweight pad forward edge coupled to and extending continuously from therear wall upper portion interior surface, wherein the weight pad forwardedge is spaced from the strike face back surface; and a lower interiorundercut extending rearwardly from the weight pad forward edge andbetween the weight pad and the sole ledge, wherein the lower interiorundercut defines a gap between the weight pad and the sole return.

Clause 22: The iron-type golf club head of clause 21, wherein the rearwall upper portion interior surface lies in a first plane.

Clause 23: The iron-type golf club head of clause 22, wherein the weightpad forward edge includes an upper region and a lower region, and atleast the upper region lies in a second plane.

Clause 24: The iron-type golf club head of clause 23, wherein the firstand second planes are co-planar.

Clause 25: The iron-type golf club head of clause 24, wherein both theupper and lower regions of the weight pad forward edge lie in the secondplane.

Clause 26: The iron-type golf club head of clause 25, wherein thefaceplate defines a loft plane, and the first and second planes areparallel to the loft plane.

Clause 27: The iron-type golf club head of clause 23, wherein the secondplane intersects the first plane.

Clause 28: The iron-type golf club head of clause 27, wherein thefaceplate defines a loft plane, and wherein the first plane is parallelto the loft plane and the second plane intersects the loft plane.

Clause 29: The iron-type golf club head of clause 8, wherein the lowerregion of the weight pad forward edge lies in a third plane, and thesecond plane intersects the third plane.

Clause 30: The iron-type golf club head of clause 29, wherein the thirdplane is parallel to the loft plane.

Clause 31: The iron-type golf club head of clause 21, wherein the rearwall lower portion exterior surface comprises a shelf surface borderingan upper end of the weight pad, the shelf surface extendingsubstantially perpendicular to the rear wall upper portion exteriorsurface.

Clause 32: The iron-type golf club head of claim 31, wherein the rearwall lower portion exterior surface comprises a back face bordering aback end of the weight pad, the back face extending between the shelfsurface and the rear body sole portion.

Clause 33: The iron-type golf club head of clause 26, wherein the rearwall upper portion thickness is between 0.025 inches and 0.040 inches.

Clause 34: The iron-type golf club head of clause 26, wherein the rearwall upper portion thickness is between 0.025 inches and 0.060 inches.

Clause 35: The iron-type golf club head of clause 26, wherein the firstplane is offset in a perpendicular direction from the loft plane at adistance between 0.200 inches and 0.300 inches.

Clause 36: The iron-type golf club head of clause 30, wherein the firstplane is offset in a perpendicular direction from the loft plane at adistance between 0.200 inches and 0.300 inches.

Clause 37: The iron-type golf club head of clause 36, wherein the thirdplane is offset in a perpendicular direction from the first plane at adistance between 0.025 inches and 0.075 inches.

Clause 38: The iron-type golf club head of clause 30, wherein an angledefined between the first plane and the second plane is between 10degrees and 20 degrees.

Clause 39: The iron-type golf club head of clause 30, wherein an angledefined between the first plane and the second plane is between 5degrees and 25 degrees.

Clause 40: The iron-type golf club head of clause 30, wherein the rearwall upper portion interior surface covers between 55% and 65% of therear wall interior surface.

Replacement of one or more claimed elements constitutes reconstructionand not repair. Additionally, benefits, other advantages, and solutionsto problems have been described with regard to specific embodiments. Thebenefits, advantages, solutions to problems, and any element or elementsthat may cause any benefit, advantage, or solution to occur or becomemore pronounced, however, are not to be construed as critical, required,or essential features or elements of any or all of the claims, unlesssuch benefits, advantages, solutions, or elements are stated in suchclaim.

Moreover, embodiments and limitations disclosed herein are not dedicatedto the public under the doctrine of dedication if the embodiments and/orlimitations: (1) are not expressly claimed in the claims; and (2) are orare potentially equivalents of express elements and/or limitations inthe claims under the doctrine of equivalents.

1. An iron-type golf club head comprising: a faceplate; a rear bodycoupled to the faceplate to form a club head body enclosing a hollowinterior cavity, the club head body defining a top rail, a sole, a heelend, a toe end, a front end, a rear end, a top rail periphery, a toeperiphery, a heel periphery, and a sole periphery; the faceplate beingdisposed at the front end and comprising a strike face, a back surfaceopposite the strike face, a leading edge proximate the sole, a solereturn extending rearward from the back surface and forming at least aportion of the sole, and a faceplate perimeter; the faceplate perimetercomprising a top perimeter edge, a heel-side perimeter edge, a toe-sideperimeter edge and a sole perimeter edge; the rear body being coupled tothe faceplate along the faceplate perimeter and including: a rear bodytop rail portion coupled to the top perimeter edge of the faceplateperimeter and forming at least a portion of the top rail; a rear bodysole portion including a sole ledge coupled to the sole perimeter edgeof the faceplate perimeter and forming at least a portion of the sole; arear body heel portion coupled to the heel-side perimeter edge of thefaceplate perimeter and forming at least a portion of the heel end, therear body heel portion including a hosel; a rear body toe portioncoupled to the toe-side perimeter edge of the faceplate perimeter andforming at least a portion of the toe end; a rear wall extending fromthe rear body sole portion to the rear body top rail portion, andbetween the rear body heel portion to the heel body toe portion, toenclose the rear end of the club head, the rear wall comprising: a rearwall upper portion comprising: a rear wall upper portion exteriorsurface; and a rear wall upper portion interior surface; wherein a rearwall upper portion thickness between the rear wall upper portionexterior surfaced and the rear wall upper portion interior surface issubstantially uniform; a rear wall lower portion comprising: a rear walllower portion exterior surface; a rear wall lower portion interiorsurface; a weight pad formed between the rear wall lower portionexterior surface and the rear wall lower portion interior surface andlocated proximate the sole, the weight pad comprising:  a weight padforward edge coupled to and extending continuously from the rear wallupper portion interior surface, wherein the weight pad forward edge isspaced from the strike face back surface; and  a lower interior undercutextending rearwardly from the weight pad forward edge and between theweight pad and the sole ledge, wherein the lower interior undercutdefines a gap between the weight pad and the sole return.
 2. Theiron-type golf club head of claim 1, wherein the rear wall upper portioninterior surface lies in a first plane.
 3. The iron-type golf club headof claim 2, wherein the weight pad forward edge includes an upper regionand a lower region, and at least the upper region lies in a secondplane.
 4. The iron-type golf club head of claim 3, wherein the first andsecond planes are co-planar.
 5. The iron-type golf club head of claim 4,wherein both the upper and lower regions of the weight pad forward edgelie in the second plane.
 6. The iron-type golf club head of claim 5,wherein the faceplate defines a loft plane, and the first and secondplanes are parallel to the loft plane.
 7. The iron-type golf club headof claim 3, wherein the second plane intersects the first plane.
 8. Theiron-type golf club head of claim 7, wherein the faceplate defines aloft plane, and wherein the first plane is parallel to the loft planeand the second plane intersects the loft plane.
 9. The iron-type golfclub head of claim 8, wherein the lower region of the weight pad forwardedge lies in a third plane, and the second plane intersects the thirdplane.
 10. The iron-type golf club head of claim 9, wherein the thirdplane is parallel to the loft plane.
 11. The iron-type golf club head ofclaim 1, wherein the rear wall lower portion exterior surface comprisesa shelf surface bordering an upper end of the weight pad, the shelfsurface extending substantially perpendicular to the rear wall upperportion exterior surface.
 12. The iron-type golf club head of claim 11,wherein the rear wall lower portion exterior surface comprises a backface bordering a back end of the weight pad, the back face extendingbetween the shelf surface and the rear body sole portion.
 13. Theiron-type golf club head of claim 6, wherein the rear wall upper portionthickness is between 0.025 inches and 0.040 inches.
 14. The iron-typegolf club head of claim 6, wherein the rear wall upper portion thicknessis between 0.025 inches and 0.060 inches.
 15. The iron-type golf clubhead of claim 6, wherein the first plane is offset in a perpendiculardirection from the loft plane at a distance between 0.200 inches and0.300 inches.
 16. The iron-type golf club head of claim 10, wherein thefirst plane is offset in a perpendicular direction from the loft planeat a distance between 0.200 inches and 0.300 inches.
 17. The iron-typegolf club head of claim 16, wherein the third plane is offset in aperpendicular direction from the first plane at a distance between 0.025inches and 0.075 inches.
 18. The iron-type golf club head of claim 10,wherein an angle defined between the first plane and the second plane isbetween 10 degrees and 20 degrees.
 19. The iron-type golf club head ofclaim 10, wherein an angle defined between the first plane and thesecond plane is between 5 degrees and 25 degrees.
 20. The iron-type golfclub head of claim 10, wherein the rear wall upper portion interiorsurface covers between 55% and 65% of the rear wall interior surface.